Loss Profile Research Articles

Loss modulation assisted solitonic pulse excitation in Kerr resonators with normal group velocity dispersion.

We demonstrate an emergent solitonic pulse generation approach exploiting the externally introduced or intrinsic loss fluctuation effects. Single or multiple pulses are accessible via self-evolution of the system in the red, blue detuning regime or even on resonance with loss perturbation. The potential well caused by the loss profile not only traps the generated pulses, but also helps to suppress the drift regarding high-order dispersion. Breathing dynamics is also observed with high driving force, which can be transferred to stable state by backward tuning the pump detuning. We further investigate the intrinsic free carrier absorption, recognized as unfavored effect traditionally, could be an effective factor for pulse excitation through the time-variant loss fluctuation in normal dispersion microresonators. Pulse excitation dynamics associated with physical parameters are also discussed. These findings could establish a feasible path for stable localized structures and Kerr microcombs generation in potential platforms.

Diabetic Neuropathy in Hands: An Endemic Complication Waiting to Unfold?

In this cross-sectional study we aimed to quantify the somatosensory dysfunction in the hand in people with diabetes with distal symmetrical polyneuropathy (DSPN) in hands and explore early signs of nerve dysfunction in people with diabetes without DSPN in hands. The clinical diagnosis of DSPN was confirmed with electrodiagnosis and corneal confocal microscopy. Thermal and mechanical nerve function in the hand was assessed with quantitative sensory tests. Measurements were compared between healthy participants (n = 31), individuals with diabetes without DSPN (n = 35), individuals with DSPN in feet but not hands (DSPNFEET ONLY) (n = 31), and individuals with DSPN in hands and feet (DSPNHANDS & FEET) (n = 28) with one-way between-group ANOVA. The somatosensory profile of the hand in people with DSPNHANDS & FEET showed widespread loss of thermal and mechanical detection. This profile in hands is comparable with the profile in the feet of people with DSPN in feet. Remarkably, individuals with DSPNFEET ONLY already showed a similar profile of widespread loss of nerve function in their hands. People with diabetes without DSPN in feet already had some nerve dysfunction in their hands. These findings suggest that nerve function assessment in hands should become more routine in people with diabetes.

Enhancing Voltage Profile and Power Loss Reduction Considering Distributed Generation (DG) Resources

In recent years, Distributed Generation (DG) has received attention due to its benefits to the distribution network. In this paper, the influence of DG along with several techniques for mitigating the detrimental impact on voltage profile and power losses was examined. The test system of 132 KV residential test feeder was selected, examined, and modeled in the Electrical Transient Analyzer Program (ETAP). Various tests were carried out to determine the influence of DG on the distribution network. Results were compared with, and without DG, taking into account the voltage profile. When injecting DG with unity power factor at different buses in a radial test system, it was discovered that when the DG of the right size and type is injected at the ideal position, the voltage profile improves while the power losses are reduced. When an un-deterministic DG is injected at multiple points on the test feeder, no improvement in voltage profile was observed. When the cross-sectional area of conductors is increased and a DG is injected at optimal locations, a positive impact on voltage profile is observed while the detrimental impact on power losses was also analyzed. The findings of this study may be useful to distribution firms regarding the future expansion of the power systems and the proliferation of DG.

Physicochemical Characterizations of Hydrolytic Degradation of Prickly Pear Seed/Polyhydroxy(Butyrate‐co‐Valerate) Biocomposite

AbstractThe present work aims at investigating the impact of hydrolytic degradation type, employing physicochemical characterizations of poly‐hydroxy (butyrate‐co‐valerate) PHBV and its biocomposites reinforced by prickly pear seed fiber (PPS), in aqueous environments to compare between seawater and distilled water. The weight loss profiles are obtained for the biocomposite immersed in seawater and distilled water of 23% and 21% respectively, however, 15% and 7% degradation for pure PHBV in seawater and distilled water, respectively. These results are explained by the addition of natural fillers to the biopolymer, which accelerates the degradation process, as well as, by the presence of microbial activity in seawater. These results are also confirmed by the Fourier transform infrared spectroscopy analysis (FTIR), by the decrease of the ester groups, which decompose into a carboxylic acid.

Universality Class of Ising Critical States with Long-Range Losses.

We show that spatial resolved dissipation can act on d-dimensional spin systems in the Ising universality class by qualitatively modifying the nature of their critical points. We consider power-law decaying spin losses with a Lindbladian spectrum closing at small momenta as ∝q^{α}, with α a positive tunable exponent directly related to the power-law decay of the spatial profile of losses at long distances, 1/r^{(α+d)}. This yields a class of soft modes asymptotically decoupled from dissipation at small momenta, which are responsible for the emergence of a critical scaling regime ascribable to the nonunitary counterpart of the universality class of long-range interacting Ising models. For α<1 we find a nonequilibrium critical point ruled by a dynamical field theory described by a Langevin model with coexisting inertial (∼∂_{t}^{2}) and frictional (∼∂_{t}) kinetic coefficients, and driven by a gapless Markovian noise with variance ∝q^{α} at small momenta. This effective field theory is beyond the Halperin-Hohenberg description of dynamical criticality, and its critical exponents differ from their unitary long-range counterparts. Our Letter lays out perspectives for a revision of universality in driven open systems by employing dark states tailored by programmable dissipation.

Trust-Based Decision-Making in the Health Context Discriminates Biological Risk Profiles in Type 1 Diabetes.

Theoretical accounts on social decision-making under uncertainty postulate that individual risk preferences are context dependent. Generalization of models of decision-making to dyadic interactions in the personal health context remain to be experimentally addressed. In economic utility-based models, interactive behavioral games provide a framework to investigate probabilistic learning of sequential reinforcement. Here, we model an economic trust game in the context of a chronic disease (Diabetes Type 1) which involves iterated daily decisions in complex social contexts. Ninety-one patients performed experimental trust games in both economic and health settings and were characterized by a multiple self-report set of questionnaires. We found that although our groups can correctly infer pay-off contingencies, they behave differently because patients with a biological profile of preserved glycemic control show adaptive choice behavior both in economic and health domains. On the other hand, patients with a biological profile of loss of glycemic control presented a contrasting behavior, showing non-adaptive choices on both contexts. These results provide a direct translation from neuroeconomics to decision-making in the health domain and biological risk profiles, in a behavioral setting that requires difficult and self-consequential decisions with health impact. Our findings also provide a contextual generalization of mechanisms underlying individual decision-making under uncertainty.

Effect of primary hole parameters on combustor performance within a slinger combustor

This study experimentally investigated the effect of the primary hole on combustor performance in a full annular slinger combustor and verified it by numerical simulation. Six primary hole structure parameters, including different numbers (0, 2, 4, 6) and positions (L/L0, 2/3L/L0, 1/3L/L0), were studied to discuss the trending of total pressure loss, ignition limits, combustion efficiency, and outlet temperature profiles, where the experiment conditions included Mach number, inlet temperature, and fuel–air ratio (FAR). Results show that when the primary hole number decreases, the total pressure loss increases, and combustion efficiency increases to a certain FAR and then drops. Successful ignition FAR and outlet temperature profiles change complicatedly, in which the trend is not consistent with the primary hole number. When L/L0 decreases, ignition limits increase, combustion efficiency drops, and outlet temperature distribution fluctuates along the circumferential direction. Numerical simulation was applied to analyse the universal impact mechanism, which proved that the primary hole parameters impact not only the airflow distribution and jet velocity but also the flow field features. A high FAR or good recirculation zone does not always lead to good performances; the compromise between aerodynamics parameters and structure characteristics determines the combustor performance.

Channel measurements and propagation characterization for indoor terahertz communication

This article presents measurements and simulations of terahertz indoor channels. The measurements are performed in two environments, line-of-sight (LoS) and reflected non-line-of-sight (RNLoS). For the LoS environment, the path loss of different distances and the influence of absorbers are investigated. For the RNLoS environment, different materials are used as reflectors. The time-frequency characteristics of indoor channels are measured by changing the transceiver angle, such as path loss, angle expansion, and power delay profile. And simulations are conducted to verify the measured data. The results show that in the LoS environment, strong multipath caused by the transmitter and receiver electronics is presented. In the RNLoS environment, the path loss is similar to the free-space path loss when the transmit angle is equivalent to the receive angle. Additionally, the results of the simulation show that the path loss changes regularly when the angle between the reflecting surface and the table changes.

Innate immune cells and myelin profile in multiple sclerosis: a multi-tracer PET/MR study.

Neuropathological studies have demonstrated distinct profiles of microglia activation and myelin injury among different multiple sclerosis (MS) phenotypes and disability stages. PET imaging using specific tracers may uncover the in vivo molecular pathology and broaden the understanding of the disease heterogeneity. We used the 18-kDa translocator protein (TSPO) tracer (R)-[11C]PK11195 and [11C]PIB PET images acquired in a hybrid PET/MR 3T system to characterize, respectively, the profile of innate immune cells and myelin content in 47 patients with MS compared to 18 healthy controls (HC). For the volume of interest (VOI)-based analysis of the dynamic data, (R)-[11C]PK11195 distribution volume (VT) was determined for each subject using a metabolite-corrected arterial plasma input function while [11C]PIB distribution volume ratio (DVR) was estimated using a reference region extracted by a supervised clustering algorithm. A voxel-based analysis was also performed using Statistical Parametric Mapping. Functional disability was evaluated by the Expanded Disability Status Scale (EDSS), Multiple Sclerosis Functional Composite (MSFC), and Symbol Digit Modality Test (SDMT). In the VOI-based analysis, [11C]PIB DVR differed between patients and HC in the corpus callosum (P = 0.019) while no differences in (R)-[11C]PK11195 VT were observed in patients relative to HC. Furthermore, no correlations or associations were observed between both tracers within the VOI analyzed. In the voxel-based analysis, high (R)-[11C]PK11195 uptake was observed diffusively in the white matter (WM) when comparing the progressive phenotype and HC, and lower [11C]PIB uptake was observed in certain WM regions when comparing the relapsing-remitting phenotype and HC. None of the tracers were able to differentiate phenotypes at voxel or VOI level in our cohort. Linear regression models adjusted for age, sex, and phenotype demonstrated that higher EDSS was associated with an increased (R)-[11C]PK11195 VT and lower [11C]PIB DVR in corpus callosum (P = 0.001; P = 0.023), caudate (P = 0.015; P = 0.008), and total T2 lesion (P = 0.007; P = 0.012), while better cognitive scores in SDMT were associated with higher [11C]PIB DVR in the corpus callosum (P = 0.001), and lower (R)-[11C]PK11195 VT (P = 0.013). Widespread innate immune cells profile and marked loss of myelin in T2 lesions and regions close to the ventricles may occur independently and are associated with disability, in both WM and GM structures.

Characterization of activated carbons for water treatment using TGA-FTIR for analysis of oxygen-containing functional groups

Water treatment with activated carbon (AC) is an established method for the removal of organic micropollutants and natural organic matter. However, it is not yet possible to predict the removal of individual pollutants. An appropriate material characterization, matching adsorption processes in water, might be the missing piece in the puzzle. To this end, this study examined 25 different commercially available ACs to evaluate their material properties. Frequently reported analyses, including N_2 adsorption/desorption, CHNS(O), point of zero charge (PZC) analysis, and X-ray photoelectron spectroscopy, were conducted on a selected subset of powdered ACs. Inorganic elements examined using X-ray fluorescence and X-ray diffraction spectroscopy revealed that relative elemental contents were distinctive to the individual AC’s raw material and activation procedure. This study also is the first to use thermogravimetric analysis (TGA) coupled to Fourier-transform infrared spectroscopy (FTIR) to conduct quantitative analyses of functional surface oxygen groups (SOGs: carboxylic acid, anhydride, lactone, phenol, carbonyl, and pyrone groups) on such a large number of ACs. The comparably economical TGA method was found to provide good surrogates for the PZC by pyrolytic mass loss up to 600 ^{circ }C (ML_{600}), for the oxygen content by ML_{1000} and for the carbon content by oxidation. Mass loss profiles depict the AC’s chemistry like fingerprints. Furthermore, we found that SOG contents determined by TGA-FTIR covered a wide individual range and depended on the raw material and production process of the AC. TGA and TGA-FTIR might therefore be used to identify the suitability of a particular AC for a variety of target substances in different target waters. This can help practitioners to control AC use in waterworks or wastewater treatment plants.

Chemical structure effects on coal pyrolyzates and reactions by using large-scale reactive molecular dynamics

The relationship between the coal chemical structure and its thermal reactivity is vital to understand coal pyrolysis behaviors. In order to explore chemical structure effects on pyrolysis process, five large-scale coal models of different ranks were constructed and simulated with ReaxFF MD simulations by a combined approach of high performance computing and cheminformatics based reaction analysis in this work. The qualitative temperature mapping results between ReaxFF MD simulations and thermogravimetry experiments were obtained for the first time through the detected covalent bond breaking, which suggests a promising scheme to map the simulation results to the real world. Importantly, the typical structures in coal can be used as the indicators to predict pyrolysis stages, weight loss profiles and major pyrolyzate distributions from the atomistic level. The starting temperature of coal thermal decomposition is anchored by the parameters of falO in 13C NMR representing alkyl ether amounts; and the largest phenol tar generation links closely to the faP NMR parameter; meanwhile methoxy groups determine the initial generation of CH3 radicals and CH4 at relatively low temperature. Additionally, the dynamic profiles of Car-Car bonds and the second increasing trend for CH3 radicals have strong relationship with recombination reactions. With the reasonable coal structures, the large-scale ReaxFF MD simulation alone can complement experimental observation comprehensively to understand the complex coal thermal chemistry and used as a preliminary screening approach to select the coal type or rank for industrial utilization.

Nutritional Status after Roux-En-Y (Rygb) and One Anastomosis Gastric Bypass (Oagb) at 6-Month Follow-Up: A Comparative Study.

Introduction: Roux-en-Y gastric bypass (RYGB) and one anastomosis gastric bypass (OAGB) are two effective bariatric surgical procedures with positive outcomes in terms of weight loss, comorbidities remission, and adverse events profiles. OAGB seems to carry a higher risk of malnutrition, but existing data are controversial. The aim of this study is to objectively evaluate and compare malnutrition in patients undergoing RYGB and OAGB. Methods: Retrospective monocentric study of obese patients undergoing RYGB or OAGB between the 15 September 2020 and the 31 May 2021. Nutritional status was assessed using the Controlling Nutritional Status (CONUT) score and compared between groups. The primary outcome was the mean CONUT score at 6 months. The secondary outcomes included the incidence of malnutrition, comorbidities, including hypertension, insulin resistance and type II diabetes mellitus, and weight loss. Results: 78 patients were included: 30 underwent RYGB and 48 underwent OAGB. At 6-Month Follow-Up there was no difference between groups in the mean CONUT score nor in incidence of malnutrition. In both groups, the nutritional status significantly worsened 6 months after surgery (preoperative and postoperative score of 0.48 ± 0.9 and 1.38 ± 1.5; p = 0.0066 for RYGB and of 0.86 ± 1.5 and 1.45 ± 1.3; p = 0.0422 for OAGB). Type II Diabetes mellitus (DMII) and hypertension remission were significant in the OAGB group with a 100% relative remission in the DMII-OAGB group (p = 0.0265), and a 67% relative remission in the hypertension-OAGB group (p = 0.0031). Conclusions: No difference in nutritional status has been detected between patients undergoing RYGB or OAGB at the 6-Month Follow-Up. Both procedures may have significant mal-absorptive effects leading to decline in nutritional status. OAGB may be more efficacious in inducing DMII and hypertension remission. Larger prospective studies dedicated specifically to nutritional status after gastric bypass are needed to confirm the impact of different bypass procedures on nutritional status.

Quantitative analysis of UV protective additives in polyethylene films by solvent extraction coupled with UV spectrophotometry

AbstractCommercial UV protective additives based on UV stabilizers (UVSs) and UV absorbers (UVAs) are used to enhance the durability of polymeric materials exposed to outdoor weathering, ultraviolet (UV) light, and heat, as in the case of agriculture films for greenhouses and water reservoirs. It is important to quantitatively study, analyze, and control the loss of these protective additives by migration and depletion from polymeric films under accelerated photodegradation and humid environments. In this study, an UVA (Tinuvin 326) and two UVSs (Chimassorb 944 FDL, and Chimassorb 911) were loaded separately in linear low‐density polyethylene (LLDPE) film and exposed to an accelerated weathering environment with ultraviolet radiation (QUV chamber). The concentration of the additives in the film before and after accelerated weathering was determined using accelerated solvent extraction and quantitatively analyzed using UV spectrophotometry. Direct quantification by FTIR spectroscopy was used on the solid films to trace the changes in the amount of the UVA and UVSs in the films following accelerated weathering exposure. Good correlation was obtained between the two methods. Using these techniques and determining each additive's loss profile, the lifetimes of polymeric films used for agriculture applications can be predicted.

Effect of lifestyle intervention in Type II diabetes

Introduction and Aim: Sedentary habits, unhealthy dietary patterns and psychological stress are the major potential problems for the advancements of a various life style disorders like Diabetes mellitus. Yoga is a lifestyle intervention, an effort to keep the condition under control and ameliorate overall quality of life. The idea of this research study among Type II diabetics is to assess the effectiveness of metabolic control with life style intervention (yoga) for 6 months. Materials and Methods: 200 subjects aged 30–60 years of either gender recently diagnosed with Type II diabetes were randomized into 4 groups and were given 6 months intervention which included supervised regular yoga practice, diet and educational sessions. Weight, BMI, glucose, HbA1c, Insulin and lipid profile were measured before commencement, and after 6 months of the intervention. The statistical methods‘t’ test and ANOVA were applied to assess the “mean and difference” at p value 0.05. Results: Alterations in the life style of Type II diabetics with the intervention of yoga, diet and educational sessions showed a significant profitable impact on weight, BMI, fasting glucose, insulin, HbA1c, and lipid profile. Conclusion: Short term interventions produced positive modest changes in metabolic control. These lifestyle modifications with the intervention of yoga and diet counselling is effective in the management of weight loss, glycemic control, plasma Insulin and lipid profile levels which on longer duration may yield a better effective result along with constant motivation.

Combined biotin, folic acid, and vitamin B12 supplementation given during the transition period to dairy cows: Part II. Effects on energy balance and fatty acid composition of colostrum and milk

Biotin (B8), folate (B9), and vitamin B12 (B12) are involved in several metabolic reactions related to energy metabolism. We hypothesized that a low supply of one of these vitamins during the transition period would impair metabolic status. This study was undertaken to assess the interaction between B8 supplement and a supplementation of B9 and B12 regarding body weight (BW) change, dry matter intake, energy balance, and fatty acid (FA) compositions of colostrum and milk fat from d -21 to 21 relative to calving. Thirty-two multiparous Holstein cows housed in tie stalls were randomly assigned, according to their previous 305-d milk yield, to 8 incomplete blocks in 4 treatments: (1) a 2-mL weekly i.m. injection of saline (0.9% NaCl; B8-/B9B12-); (2) 20 mg/d of dietary B8 (unprotected from ruminal degradation) and 2-mL weekly i.m. injection of 0.9% NaCl (B8+/B9B12-); (3) 2.6 g/d of dietary B9 (unprotected) and 2-mL weekly i.m. injection of 10 mg of B12 (B8-/B9B12+); (4) 20 mg/d of dietary B8, 2.6 g/d of dietary B9, and 2-mL weekly i.m. injection of 10 mg of B12 (B8+/B9B12+) in a 2 × 2 factorial arrangement. Colostrum was sampled at first milking. and milk samples were collected weekly on 2 consecutive milkings and analyzed for FA composition. Body condition score and BW were recorded every week throughout the trial. Within the first 21 d of lactation, B8-/B9B12+ cows had an increased milk yield by 13.5% [45.5 (standard error, SE: 1.8) kg/d] compared with B8-/B9B12- cows [40.1 (SE: 1.9)], whereas B8 supplement had no effect. Even though body condition score was not affected by treatment, B8-/B9B12+ cows had greater BW loss by 24 kg, suggesting higher mobilization of body reserves. Accordingly, milk de novo FA decreased and preformed FA concentration increased in B8-/B9B12+ cows compared with B8-/B9B12- cows. In addition, cows in the B8+/B9B12- group had decreased milk de novo FA and increased preformed FA concentration compared with B8-/B9B12- cows. Treatment had no effect on colostrum preformed FA concentration. Supplemental B8 decreased concentrations of ruminal biohydrogenation intermediates and odd- and branched-chain FA in colostrum and milk fat. Moreover, postpartum dry matter intake for B8+ cows tended to be lower by 1.6 kg/d. These results could indicate ruminal perturbation caused by the B8 supplement, which was not protected from rumen degradation. Under the conditions of the current study, in contrast to B8+/B9B12- cows, B8-/B9B12+ cows produced more milk without increasing dry matter intake, although these cows had greater body fat mobilization in early lactation as suggested by the FA profile and BW loss.

The emotional impact of disrupted environmental contexts: Enrichment loss and coping profiles influence stress response recovery in Long-Evans rats.

With increasing rates of anxiety and mood disorders across the world, there is an unprecedented need for preclinical animal models to generate translational results for humans experiencing disruptive emotional symptoms. Considering that life events resulting in a perception of loss are correlated with depressive symptoms, the enrichment‐loss rodent model offers promise as a translational model for stress‐initiated psychiatric disorders. Additionally, predisposed temperament characteristics such as coping styles have been found to influence an individual's stress response. Accordingly, male rats were profiled as either consistent or flexible copers and assigned to one of three environments: standard laboratory housing, enriched environment, or enriched environment exposure followed by downsizing to standard laboratory cages (i.e., enrichment‐loss group). Throughout the study, several behaviors were assessed to determine stress, social, and reward‐processing responses. To assess recovery of the stress response, fecal samples were collected following the swim stress in 3‐h increments to determine the recovery trajectory of corticosterone (CORT) and dehydroepiandrosterone (DHEA) metabolite levels. Upon death, neural markers of neuroplasticity including doublecortin, glial fibrillary acidic factor, and brain‐derived neurotrophic factor were assessed via immunohistochemistry. Results indicated the flexible coping animals in the continuous enriched group had higher DHEA/CORT ratios (consistent with adaptive responses in past research); furthermore, the enrichment‐loss animals exhibited a blunted CORT response throughout the assessments and enriched flexible copers had faster CORT recovery rates than consistent copers. Standard housed animals exhibited less exploratory behavior in the open field task and continuous enriched, flexible rats consumed more food rewards than the other groups. No differences in neuroplasticity neural markers were observed. In sum, the results of the present study support past research indicating the disruptive consequences of enrichment‐loss, providing evidence that the model represents a valuable approach for the investigation of neurobiological mechanisms contributing to interindividual variability in responses to changing experiential landscapes.

Electronic energy loss and ion velocity correlation effects in track production in swift-ion-irradiated LiNbO3: A quantitative assessment between structural damage morphology and energy deposition

• Essential factors including electronic energy loss and ion velocity co-affect latent track damage. • Damage morphologies from spherical defects to discontinuous and continuous tracks are confirmed. • Atomic energy deposition and temperature evolution are determined by inelastic thermal spike model. • A quantitative relationship between ion irradiation condition and track damage response is proposed. • The work provides a deeper insight for understanding ion-solid interactions and damage behaviors. The primary motivation for studying how irradiation modifies the structures and properties of solid materials involves the understanding of undesirable phenomena, including irradiation-induced degradation of components in nuclear reactors and space exploration, and beneficial applications, including material performance tailoring through ion beam modification and defect engineering. In this work, the formation mechanism of latent tracks with different damage morphologies in LiNbO 3 crystals under 0.09–6.17 MeV/u ion irradiation with an electronic energy loss from 2.6–13.2 keV/nm is analyzed by experimental characterizations and numerical calculations. Irradiation-induced damage is preliminarily evaluated via the prism coupling technique to analyze the correlation between the dark-mode spectra and energy loss profiles of irradiated regions. Under the irradiation conditions of different ion velocities and electronic energy losses, different damage morphologies, from individual spherical defects to discontinuous and continuous tracks, are experimentally characterized. During ion penetration process, the ion velocity determines the spatiotemporal distribution of deposited irradiation energy induced by electronic energy loss, meaning that the two essential factors including electronic energy loss and ion velocity co-affect the track damage. The inelastic thermal spike model is used to numerically calculate the spatiotemporal evolutions of energy deposition and the corresponding atomic temperature under different irradiation conditions, and a quantitative relationship is proposed by comparison with corresponding experimentally observed track damage morphologies. The obtained quantitative relationship between irradiation conditions and track damage provides deep insight and guidance for understanding the damage behavior of crystal materials in extreme radiation environments and selecting irradiation parameters, including ion species and energies, for ion beam technique application in atomic-level defect manipulation, material modification, and micro/nanofabrication.

Ash composition, structural characteristics and thermal conversion performance of Texaco gasifier based on Zhundong coal

Composition and structure characteristics of fine slag (FS) and coarse slag (CS) discharged from Texaco gasifier with Zhundong coal as raw material were analyzed, and their thermochemical conversion properties were analyzed. Proximate and ultimate analyses show that the contents of fixed carbon in coarse slag are 42.31%, indicating that it can be used as raw material to realize its high-added utilization. Analysis with Fourier transform infare spectrometer (FT-IR) suggest that the absorption peak of Si-O in coarse slag and fine slag is stronger, and there is a small amount of aromatic structure in fine slag. Thermal decomposition behaviors in inert atmosphere show that the maximum weight loss rate peak of coarse slag is located around 600 °C, while that of fine slag is transferred to about 620 °C. Results of thermal decomposition in oxidization atmosphere show that there are obvious weight loss rate peaks derived from combustion of the fixed carbon in 500–700 °C. The weight loss profiles of fine slag and coarse slag in inert and oxidization atmosphere were fitted by Coats-Redfern method. The kinetic parameters including pyrolysis/combustion activation energy and correlation coefficient were calculated. The results show that the fitting effect is better as the reaction order selected as 3 at the intense pyrolysis section (560–640 °C) for coarse slag in inert atmosphere, with correlation coefficient R2 of 0.99 and activation energy E of 38.85 kJ/mol. Similarly, in the intense pyrolysis stage (590–650 °C) of fine slag, the fitting effect is better as the reaction order selected 3, with the correlation coefficient R2 of 0.97 and the activation energy E of 79.09 kJ/mol. In oxidization atmosphere, at the intense combustion stage of coarse slag (540–605 °C) and fine slag (530–605 °C), the fitting effect is better as n=1 for the both slags, with the activation energy E of 226.46 and 154.73 kJ/mol respectively.

Influence of Wake Intensity on the Unsteady Flow Characteristics of the Integrated Aggressive Interturbine Duct

The interturbine transition duct (ITD), located between the high-pressure (HP) and low-pressure (LP) turbines of aeroengines, tends to be designed as an aggressive ITD integrated with wide-chord struts to meet the requirements of civil aeroengines for high bypass ratios and thrust–weight ratios. This paper presents a detailed unsteady numerical investigation of the effects of the HP rotor trailing-edge radius on the unsteady flow characteristics in the integrated aggressive interturbine transition duct (AITD), including the transport and dissipation of HP rotor wakes, the control mechanism of HP rotor wakes on flow separation and the influence of wake parameters. A sweeping rod, with a nondimensional diameter ranging from d/s = 0.056~0.143 (based on the pitch (s) of wide-chord struts at the midspan) and a reduced frequency (f) of 1.07, is used to simulate the HP rotor wake to decouple its influence from other secondary flows. Using the k-ω SST turbulence model and gamma–theta transition model, a structured grid with 6.3 million nodes can achieve similar global results. The wake in the lower part of the AITD channel dissipates rapidly because of the stretching between its own circumferential motion and the radial upward secondary flow, especially for a small d/s. Only the residual wake in the upper part can reach wide-chord struts in the case with large d/s. A sweeping rod with a large d/s can reduce the radial pressure gradient in the AITD, inhibit the internal secondary flow to a certain extent, reduce the dissipation rate of the wake, enhance its suppression effect on flow separation on a wide-chord strut, and decrease the flow loss. However, the wake can also enhance the passage vortex due to the increasing circumferential pressure gradient in the wide-chord strut channel, resulting in increasing blade profile loss. In the scope of this study, the aerodynamic gain of the wake is still not enough to compensate for its loss increment (including its own dissipation loss). Therefore, selecting a small trailing-edge radius of the HP rotor is conducive to improving the aerodynamic performance of the integrated AITD.

The Optimization of Gelatin Extraction from Chicken Feet and the Development of Gelatin Based Active Packaging for the Shelf-Life Extension of Fresh Grapes

Synthetic plastics are causing serious environmental and health problems due to which the concept of developing biodegradable food packaging has gained considerable attention. In this study, extraction of gelatin from chicken feet was optimized followed by characterization of gelatin. Chicken feet gelatin was used to develop biodegradable nanocomposite films by the incorporation of chitosan (CS) and zinc oxide (ZnO) nanoparticles (NPs). Gelatin nanocomposite films were used to increase the shelf-life of fresh grapes by determining the browning index, weight loss, and microbial profile of fresh grapes. A high yield (7.5%) of gelatin and Bloom strength (186 g) were obtained at optimized extraction conditions (pretreatment with 4.2% acetic acid and extraction at 66 °C for 4.2 h). Electrophoretic analysis of gelatin revealed the presence of α (130–140 kDa) and β chains (195–200 kDa), whereas a Fourier transformed infrared (FTIR) spectrometer confirmed the presence of amide A and B and amide I, II, and III. Incorporation of ZnO NPs in a gelatin–CS matrix improved the barrier and the mechanical and the thermal properties of films. Gelatin nanocomposite films with 0.3% ZnO NPs significantly reduced the weight loss (23.88%) and the browning index (53.33%) of grapes in comparison to control treatments. The microbial count in artificially inoculated grapes wrapped in gelatin nanocomposite films remained below 4 log CFU/mL until the fifth storage day in comparison to control treatments. The gelatin from poultry byproducts such as chicken feet can serve as an efficient biopolymer to develop biodegradable food packaging to enhance the shelf-life of perishable food products.