High Bath Research Articles

Application of DPG/KH550 modified pyrolysis carbon black in oil and high temperature‐resistant NBR composites

AbstractIn this paper, pyrolysis carbon black (CBp) was introduced into nitrile butadiene rubber (NBR), the effects of the ratio of CBp and carbon black (N326) on the properties of NBR composites were investigated, and the optimal ratio was determined. On this basis, the accelerator DPG, coupling agent KH550 and CBp were modified by ball milling and plasma. The results showed that when the ratio of CBp to N326 was 40:15, the overall properties of NBR composites was better. Compared with the unmodified CBp/NBR composites, the change rate of tensile product, resilience and DIN abrasion of ball milling‐plasma modified CBp/NBR composites in oil environment were reduced by 52.96%, 12.81%, and 27.19%, respectively, and the tear strength after double damage by high temperature and oil bath was increased by 15.63%, which resulted in better oil and high temperature‐resistance. In summary, the ball milling‐plasma combined with DPG/KH550 modified CBp can not only replace N326 carbon black, but also realize the preparation of NBR composites with better oil and high temperature‐resistance.

7987 Ravenous Bone

Abstract Disclosure: Y. Oo: None. L. Srisawitri: None. P. Patel: None. M. Thein: None. Introduction Hungry bone syndrome ( HBS ) is the rapid drop in serum total calcium concentration of less than 2.1 mmol/L and/or prolonged hypocalcemia for more than 4 days postparathyroidectomy. It is more frequent in hemodialysis patients with secondary hyperparathyroidism (SHPT). The severe hypocalcemia after the parathyroidectomy is believed to be due to the increased usage of calcium by the starving bones. The key management is to replenish the severe calcium deficit aggressively. Clinical Case A 44-year-old Hispanic male patient with ESRD on hemodialysis was admitted for elective parathyroidectomy for SHPT from ESRD. The hospital course was complicated with profound hypocalcemia after the surgery. The pertinent lab results before surgery were total calcium level of 7.2 mg/dl ( normal 8.4 - 10.2 ), ionized calcium level of 4.9 ( normal 4.48 - 4.92 ), and PTH level of 2184 pg/ml (normal 15 - 65). After the parathyroidectomy, the ionized calcium level became 3.4 mg/dl and the PTH level trended down to 56 pg/ml. On the post-op day ( POD ) 1, the patient was started on calcitriol 1 mcg BID and calcium carbonate 600 mg QID and also got the hemodialysis with a high calcium bath. Even with the replacement, the calcium level kept worsening and calcium gluconate infusion was started on POD 4. On POD 5, calcium gluconate infusion was on hold as the ionized calcium was improved. On POD 7, calcitriol was increased to 2 mcg BID as ionized calcium was 3.2 mg/dl and restarted on calcium gluconate infusion. On POD 8, ionized calcium was 3.5 mg/dl, and calcium gluconate infusion was titrated down. On POD 9, as the total calcium level was 8.8 mg/dl, the calcium gluconate infusion was discontinued and he was discharged with calcium carbonate 1200 mg TID and calcitriol 2 mcg TID. Unfortunately, 13 days from the discharge date, he was readmitted with the volume overload, and on this second admission, the total calcium was 7 mg/dl and ionized calcium was 3.2 mg/dl. The calcitriol dose was increased to 2 mcg TID and the same dose of calcium carbonate which was 1200 mg TID. He got hemodialysis with a high calcium bath. After being treated for the volume overload, he was discharged with calcitriol 2 mcg TID and calcium carbonate 1200 mg TID and followed up with the endocrinology team in 2 weeks. Conclusion Even with the aggressive and constant replacement of calcium, the HBS cases are challenging in terms of achieving and maintaining a normal calcium level after surgery. We, the clinicians, need a better understanding of how to avoid the development of HBS or at least minimize the severity of hypocalcemia in the postoperative course and the ultimate management regimen to maintain the normal calcium level in both inpatient and outpatient settings. Presentation: 6/1/2024

Migration and Separation of Polymers in Nonuniform Active Baths.

Polymerlike structures are ubiquitous in nature and synthetic materials. Their configurational and migration properties are often affected by crowded environments leading to nonthermal fluctuations. Here, we study an ideal Rouse chain in contact with a nonhomogeneous active bath, characterized by the presence of active self-propelled agents which exert time-correlated forces on the chain. By means of a coarse-graining procedure, we derive an effective evolution for the center of mass of the chain and show its tendency to migrate toward and preferentially localize in regions of high and low bath activity depending on the model parameters. In particular, we demonstrate that an active bath with nonuniform activity can be used to separate efficiently polymeric species with different lengths and/or connectivity.

Investigating the effect of anchoring groups modified comb-like polycarboxylate hyperdispersants on dispersion and stability in dispersed dyes

Comb-like hyperdispersants are widely used for the dispersion of liquid dispersed dyes (LDDs), because of the molecular structure of comb, in which the effective steric hindrance effects provided by polymer side chains and the adsorption force provided by anchoring groups, resulting in the dispersant to be firmly adsorbed on the surface of the dye. However, the mechanism by which the anchoring groups in this dispersant affect the dispersion and stability of LDDs is still unclear. Herein, three types of anchoring group modified comb-like polycarboxylate hyperdispersants were synthesized to explore the effect of anchoring groups on stability and dispersibility, in which the anchoring groups from the monomers of 2-vinylnaphthalene (2-VNP), styrene (St), and 4-vinylbiphenyl (4-VBP). The optimal sand grinding conditions and dispersion stability of the modified hyperdispersants were comprehensively investigated. 2-VNP modified hyperdispersant (DPN) possessed higher grinding efficiency and better dispersion stability than those of St (DPS) and 4-VBP modified hyperdispersants (DPB). The results of atomic force microscope (AFM) and quartz crystal microbalance (QCM) indicated that DPN exhibited higher adsorption force (2.16 mN/m) than that the DPS (0.648 mN/m) and DPB (1.56 mN/m), thereby improving the adsorption strength of dispersants and DDs, stabling the dispersion effect of LDDs. In addition, the dyeing performance of the prepared LDDs on polyester fabric was further investigated. It was found that these LDDs acquired a faster dyeing rate, higher K/S values and rubbing color fastness, and lower chemical oxygen demand (COD) of residual liquid than commercial powder DDs, due to the higher adsorption force on the DDs surface provided good colloidal stability in the high temperatures dye bath. We expect that this study will provide important mechanistic insights into the development of hyperdispersants for LDDs controlled by high adsorption force anchoring groups.

FedFSA: Hybrid and federated framework for functional status ascertainment across institutions

IntroductionPatients' functional status assesses their independence in performing activities of daily living, including basic ADLs (bADL), and more complex instrumental activities (iADL). Existing studies have discovered that patients’ functional status is a strong predictor of health outcomes, particularly in older adults. Depite their usefulness, much of the functional status information is stored in electronic health records (EHRs) in either semi-structured or free text formats. This indicates the pressing need to leverage computational approaches such as natural language processing (NLP) to accelerate the curation of functional status information. In this study, we introduced FedFSA, a hybrid and federated NLP framework designed to extract functional status information from EHRs across multiple healthcare institutions. MethodsFedFSA consists of four major components: 1) individual sites (clients) with their private local data, 2) a rule-based information extraction (IE) framework for ADL extraction, 3) a BERT model for functional status impairment classification, and 4) a concept normalizer. The framework was implemented using the OHNLP Backbone for rule-based IE and open-source Flower and PyTorch library for federated BERT components. For gold standard data generation, we carried out corpus annotation to identify functional status-related expressions based on ICF definitions. Four healthcare institutions were included in the study. To assess FedFSA, we evaluated the performance of category- and institution-specific ADL extraction across different experimental designs. ResultsADL extraction performance ranges from an F1-score of 0.907 to 0.986 for bADL and 0.825 to 0.951 for iADL across the four healthcare sites. The performance for ADL extraction with impairment ranges from an F1-score of 0.722 to 0.954 for bADL and 0.674 to 0.813 for iADL across four healthcare sites. For category-specific ADL extraction, laundry and transferring yielded relatively high performance, while dressing, medication, bathing, and continence achieved moderate-high performance. Conversely, food preparation and toileting showed low performance. ConclusionNLP performance varied across ADL categories and healthcare sites. Federated learning using a FedFSA framework performed higher than non-federated learning for impaired ADL extraction at all healthcare sites. Our study demonstrated the potential of the federated learning framework in functional status extraction and impairment classification in EHRs, exemplifying the importance of a large-scale, multi-institutional collaborative development effort.

Preparation and Properties of Porous Concrete Based on Geopolymer of Red Mud and Yellow River Sediment.

Red mud (RM) and Yellow River sediment (YRS) are challenging to handle as waste materials. In this study, RM with geopolymer and heavy metal adsorption characteristics was combined with YRS and ground granulated blast furnace slag (GGBS) to develop a porous geopolymer with high strength and high adsorption performance. A geopolymer cementitious material with high strength was prepared using high temperature water bath curing of 90 °C and different dosages of YRS, and a porous geopolymer concrete was further prepared. The compressive strength, fluidity and setting time of geopolymer cementitious materials were tested, and the compressive strength, porosity and permeability of porous geopolymer concrete were also tested. The environmental impact assessment of geopolymer cementitious materials was further conducted. The hydration products and microstructure of geopolymer gel materials were analyzed by XRD, SEM and FT-IR tests. The results show that the addition of YRS can effectively prolong the setting time of the geopolymer cementitious material, and the enhancement rate is as high as 150% compared with the geopolymer cementitious materials without the addition of YRS. An appropriate amount of YRS can improve the compressive strength of the geopolymer cementitious materials, and its early compressive strength can be further improved under the high temperature water bath curing of 90 °C, and the compressive strength at an age of 3 d can be up to 86.7 MPa. Meanwhile, the compressive strength of porous geopolymer concrete at an age of 28 d is up to 28.1 MPa. YRS can participate in geopolymer reactions, and high temperature water bath curing can promote the reaction degree. Curing method and YRS dosages have little effect on the porosity and permeability of the porous geopolymer concrete. The porous geopolymer has a good heavy metal adsorption effect, and the alkaline pH values can be gradually diluted to neutral.

Preliminary Evaluation of Methods for Continuous Carbon Removal from a Molten Catalyst Bubbling Methane Pyrolysis Reactor

Methane pyrolysis in molten catalyst bubble (MCB) column reactors is an emerging technology that enables the simultaneous production of hydrogen and solid carbon, together with a mechanism for separating the two coproducts. In this process, methane is dispersed as bubbles into a high temperature molten catalyst bath producing hydrogen and low-density carbon, which floats to the surface of the bath from providing a means for them to be separated. However, the removal of carbon particulates from a bubbling column reactor is technically challenging due to the corrosive nature of the molten catalysts, contamination of the product carbon with the molten catalysts, high temperatures and lack of understanding of the technology options. Four potential concepts for the removal of carbon particulate from a methane pyrolysis molten metal bubble column reactor are presented, based on the pneumatic removal of the particles or their overflow from the reactor. The concepts are evaluated using a cold prototype reactor model. To simulate the operation of a high-temperature reactor at low temperatures, the dominant dimensionless numbers are identified and matched between a reference high-temperature reactor and the developed cold prototype using water, air and hollow glass microsphere particles as the representatives of the molten catalyst, gaseous phases and solid carbon particulates, respectively. The concepts are tested in the cold prototype. High rates of particle removal are achieved, but with different tradeoffs. The applicability of each method together with their advantages and disadvantages are discussed.

Glutamate Spillover Dynamically Strengthens Gabaergic Synaptic Inhibition of the Hypothalamic Paraventricular Nucleus.

The hypothalamic paraventricular nucleus (PVN) is strongly inhibited by γ-aminobutyric acid (GABA) from the surrounding peri-nuclear zone (PNZ). Because glutamate mediates fast excitatory transmission and is substrate for GABA synthesis, we tested its capacity to dynamically strengthen GABA inhibition. In PVN slices from male mice, bath glutamate applied during ionotropic glutamate receptor blockade increased PNZ-evoked inhibitory postsynaptic currents (eIPSCs) without affecting GABA-A receptor agonist currents or single-channel conductance, implicating a presynaptic mechanism(s). Consistent with this interpretation, bath glutamate failed to strengthen IPSCs during pharmacological saturation of GABA-A receptors. Presynaptic analyses revealed that glutamate did not affect paired-pulse ratio, peak eIPSC variability, GABA vesicle recycling speed, or readily releasable pool (RRP) size. Notably, glutamate-GABA strengthening (GGS) was unaffected by metabotropic glutamate receptor blockade and graded external Ca2+ when normalized to baseline amplitude. GGS was prevented by pan- but not glial-specific inhibition of glutamate uptake and by inhibition of glutamic acid decarboxylase (GAD), indicating reliance on glutamate uptake by neuronal excitatory amino acid transporter 3 (EAAT3) and enzymatic conversion of glutamate to GABA. EAAT3 immunoreactivity was strongly localized to presumptive PVN GABA terminals. High bath K+ also induced GGS, which was prevented by glutamate vesicle depletion, indicating that synaptic glutamate release strengthens PVN GABA inhibition. GGS suppressed PVN cell firing, indicating its functional significance. In sum, PVN GGS buffers neuronal excitation by apparent "over-filling" of vesicles with GABA synthesized from synaptically released glutamate. We posit that GGS protects against sustained PVN excitation and excitotoxicity while potentially aiding stress adaptation and habituation.

Unraveling the Fundamental Concepts of Superaerophobic/Superhydrophilic Electrocatalysts for Highly Efficient Water Electrolysis: Implications for Future Research

AbstractElectrochemical water splitting is a highly effective method for carbon‐free hydrogen production. While significant efforts have been made to develop efficient and cost‐effective electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), the optimization of electrode surface properties has been largely overlooked. Inadequate mass diffusion, especially at high bath voltage, hampers the energy transfer efficiency of water electrolysis. To overcome these challenges, precise design of superaerophobic/superhydrophilic electrodes can effectively separate gas bubbles from the catalyst surface and enhance mass transfer, improving overpotential and Faraday efficiency. This article underscores the importance of designing electrocatalysts with well‐designed surface properties to address these challenges. It also discusses characterization techniques for evaluating surface properties and provides examples of applications for superaerophobic/superhydrophilic electrodes in energy storage and conversion systems, electrochemical biosensors, and industrial processes, etc. Overall, optimizing the surface properties of electrocatalysts holds promise for enhancing the efficiency of gas‐involving reactions and energy conversion systems.

Effect of trimethylamine borane (TMAB) bath concentration on electrodeposited Ni–B/TiC nanocomposite coatings

In this study, stainless steel material was coated with Ni–B alloy-based, TiC particle reinforced composite film using electrochemical deposition method. The properties of the obtained Ni–B/TiC nanocomposite coatings were investigated in terms of the effect of trimethylamine borane (TMAB) bath concentration, which is a boron source. In addition, the data of pure Ni, Ni–B alloy and stainless steel are presented together for comparison. According to the cyclic voltammogram (CV) analysis, it is seen that TMAB contributes to increasing the deposition rate. In the crystal structure analysis, the effect of TMAB was weaker at low TiC bath concentrations, while the effect of TMAB was more dominant at high TiC bath contents. The crystal grain size values of nanocomposite coatings vary between 5.8 and 16.8 nm, and these values decrease up to 86% when compared to the crystal grain size of the pure Ni coating. Although the increase in TMAB initially causes an increase in the microhardness of nanocomposite coatings, when the TMAB value was further increased, it was observed that the microhardness decreased even more compared to the previous initial value. The highest hardness value was obtained in the sample produced at 5 g/l TiC and 6 g/l TMAB bath contents, and this value was 817 HV. Compared to this value, it was observed that the hardness of pure Ni was 65% lower. It was observed that TMAB did not have significant effect on the coating morphology, but the increase in TMAB caused an increase B content and a decrease in the TiC content in the nanocomposite coating. Furthermore, it was revealed that the increase in TMAB bath concentration caused an improvement on corrosion resistance. The corrosion current of the composite sample with 9 g/l TMAB concentration, which showed the best corrosion performance, decreased by 85% compared to pure nickel.

Stochastic learning control of adiabatic speedup in a non-Markovian open qutrit system

Precise and efficient control of quantum systems is essential to perform quantum information-processing tasks. In terms of adiabatic speedup via leakage elimination operator approach, for a closed system, the ideal pulse control conditions have been theoretically derived by P-Q partitioning technique. However, it is a challenge to design the corresponding control pulses for an open system, which requires noisy environments to be addressed. In this paper, we apply the stochastic search procedures to an open qutrit system and successfully obtain the optimal control pulses for significant adiabatic speedup. The calculation results show that these optimal pulses allow us to acquire higher fidelities than the ideal pulses. The improvement of fidelity is large for relatively strong system-bath coupling strength and high bath temperature. For certain coupling strength and bath temperature, the maximal improvement can be achieved for a critical characteristic frequency which represents the memory time of the environment. Our investigation indicates that the stochastic search procedures are powerful tools to design control pulses for combating the detrimental effects of the environment.

PSUN16 Sublethal Hyperthermia Decreases Cellular Proliferation and Transiently Disrupts Steroidogenesis in Adrenal Cells

Abstract Introduction Primary Aldosteronism is the most common cause of secondary hypertension. First-line treatment; adrenalectomy resects adrenal nodules and adjacent normal tissue, limiting suitability to those who present with unilateral disease. Use of thermal ablation represents an emerging approach as a possible minimally invasive therapy for unilateral and bilateral disease, to target and disrupt hypersecreting aldosterone producing adenomas, while preserving adjacent normal adrenal cortex. Ablation involves heating tissue >50°C to induce cellular necrosis. Outside the core ablation zone, the transitional zone is an area exposed to variable temperatures between 37°C – 50°C. To understand the feasibility of precision ablation in the adrenal gland, we examined the effect of applying these temperatures to adrenocortical cells to identify i) the required temperature to effectively ablate adrenal cells ii) the extent of damage that may occur to surrounding healthy adrenal cells with exposure to transitional zone temperatures. Methods Steroidogenic adrenocortical cell lines, H295R and HAC15, were treated with hyperthermia (high precision water bath) at temperatures of 37, 42, 45, 48 and 50°C and steroidogenesis was subsequently stimulated using forskolin (10µM) and angiotensin II (10nM). Cell death (Propidium iodide staining by flow cytometry), proliferation (xCELLigence real-time cell analysis), protein expression (Western blot/qRT-PCR), and steroid secretion (HPLC-Mass spectrometry) were analysed immediately and 7-days post-treatment. Results Cell death occurred at 48°C and 50°C (p<0.05 vs 37°C control), but not 45°C, or 42°C. Sublethal hyperthermia (42°C and 45°C for 30 minutes) induced a heat shock response demonstrated by upregulation of HSP70 and HSP90. Proliferation was subsequently reduced over 7-days alongside a decrease in aldosterone and cortisol secretion (p<0.05), and reduced expression of steroidogenic enzymes (CYP11B1, CYP11B2, CYP11A1) 18-hours post treatment (p<0.05). Following 7-days sublethal hyperthermia, steroid secretion and steroidogenic enzymatic expression returned to baseline levels. Conclusion Hyperthermia at 48°C and 50°C for 15 minutes is required for sustained cell death at 7-days post treatment. Sublethal hyperthermia, equivalent to that produced in the transitional zone during thermal ablation, produces a short-lived unsustained inhibition of steroidogenesis that recovers 7-days post treatment. Therefore, segmental adrenal sparing ablation is possible with recovery of transitional zone following ablation. This underlines the potential for precision technology development for bilateral adrenal ablation as definitive measure to treat PA caused by APA or Micronodular disease. Presentation: Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m.

EXPERIMENTAL INVESTIGATION of DOUBLE AGING HEAT TREATMENT of INCONEL 718 MONOBLOCK GAS TURBINE DISC IN A SALT BATH

The heat treatment of Inconel 718 (In718) monoblock gas turbine discs are mainly done by vacuum furnaces. Despite the vacuum furnaces allow to make a clean and reliable heat treatment, its operation costs affects the final product’s cost. In this work, as an alternative to the vacuum furnaces, the double aging heat treatment of In718 disc in a salt bath was investigated. The appropriate temperature for high and low temperature salt bath was identified in order to achieve necessary cooling rates of 125°C/min and 120°C/min for a 400 kg workpiece. It is shown that the heat treatment could be done when the high and low temperature salt baths temperatures are equal to 300°C. It is also found that the heat transfer coefficient for simulation could be taken as 650 W/m2.K regardless to the salt bath temperature.

Thermal local Fisher information and quantum uncertainty in Heisenberg model

This study explores the spontaneous emergence of local Fisher information and local quantum uncertainty beyond entanglement in a noisy two-qubit Heisenberg XXX model with Dzyaloshinskii-Moria (DM) and Kaplan-Shekhtman-Entin-Wohlman-Aharony (KSEA) interactions. Local quantum Fisher information, local quantum uncertainty, and logarithmic negativity are used to examine two-spin non-locality. We find that by employing strong two-spin, Dzyaloshinskii- Moriya, and Kaplan-Shekhtman-Entin-Wohlman-Aharony interactions, we can prevent noise-induced losses in local Fisher information, local quantum uncertainty, and logarithmic negativity. The robustness of the two-spin non-localities is greater for a strong spin’s coupling strength than for the strong DM and KSEA interactions. Local Fisher information and local quantum uncertainty, as well as logarithmic-negativity, display asymmetric behaviors with respect to two-spin coupling and symmetric behaviors with respect to the Dzyaloshinskii-Moriya and Kaplan-Shekhtman-Entin-Wohlman-Aharony interactions. At high bath temperatures, the phenomenon of sudden-death two-spin entanglement emerges. Furthermore, by combining the parameters of the strong two-spin, DM, and KSEA interactions, the robustness of the produced two-spin non-localities can be improved.

Comparison of non-radiographic axial spondyloarthritis and ankylosing spondylitis patients in Malaysia

Aim of the workThis study aimed to compare the clinical features, associated comorbidities and treatment patterns of ankylosing spondylitis (AS) patient to those with non-radiographic axial spondyloarthritis (nr-axSpA) in Malaysia. Patients and methodsThis study was conducted in multiple rheumatology centre in Malaysia. Patients with axial spondyloarthritis (axSpA) were included. The AS and nr-axSpA group were compared. ResultsA total of 302 AS patients and 43 nr-axSpA patients were included. The age was comparable (41.7 ± 12.4 vs 38.5 ± 14.3 years; p = 0.13) however the male:female in those with AS was 4.8:1 vs 1.2:1 (p < 0.0001). The diagnostic delay was longer in AS patients (6.04 ± 6.6 vs 3.4 ± 7.3; p = 0.03), more were frequently smoking (50.3 % vs 25.6 %; p = 0.003), were Chinese (56.6 % vs 37.2 %; p = 0.02), had a higher frequency of HLA-B27 (p < 0.0001) and family history of axSpA (p = 0.04).More AS patients experienced inflammatory back pain (p < 0.0001), had higher Bath AS Metrology Index (BASMI) (p < 0.0001) and Bath AS functional index (BASFI) (p = 0.04). Nr-axSpA patients more likely to experience dactylitis (16.3 % vs 5.6 %; p = 0.014) but no significant differences in frequency of enthesitis. The frequency of comorbidities was similar in both groups. The use of non steroidal anti inflammatory drugs was more frequent in AS (p = 0.038) while nr-axSpA patients more likely to receive conventional disease modifying antirheumatic drug (p = 0.002). ConclusionAS and nr-axSpA shared some characteristics but also had some significant difference especially on gender, inflammatory back pain and HLA-B27. This study offers a better understanding of both the subtypes of axSpA in Malaysia.

Finite Element Analysis and Polarization Test of IDEs Piezoelectric Actuator.

A new type of actuator is presented in the paper that integrates the IDEs into a conventional piezoelectric sheet. The electrodes and polarization play a key role in the strain. Adopting constitutive equations of piezoelectric theory and variation principles in elasticity theory, the piezoelectric component dynamic equation was deduced. Several finite element models of the IDEs piezoelectric actuator were established in ANSYS. The effect of branch electrodes on the strain of the actuator was analyzed. The results show that the strain can be bigger than that of the conventional piezoelectric sheet by decreasing the gap and increasing the width of electrodes. According to the FEM result, some IDEs piezoelectric actuators were prepared. The distribution of the static electric field inside the actuator was researched to determine the polarization voltage. The 2671 high voltage power and DU-20 temperature-controlled oil bath was applied to explore the polarization process. The effect of the voltage, time and temperature on the strain of the actuator was researched by a TF2000 and SIOS laser interferometer. The results show that the optimum polarization is 800 V, for 60 min and at 150 °C. The strain of the IDEs piezoelectric actuator is 1.87 times that of the conventional piezoelectric actuator. The actuators could prove to be helpful applications for micro-nano devices.

Quantification of different quantum correlations in a double cavity optomechanical system

The aim of this paper is to quantify the quantum correlations between mechanical and optical modes in an optomechanical system with two spatially separated Fabry–Pérot cavities. We use logarithmic negativity [Formula: see text] and entanglement of formation (EoF), respectively, to quantify entanglement between optical and mechanical modes, while Gaussian geometric discord (GGD) is used to capture all nonclassical correlations, including entanglement. These quantifiers are evaluated as functions of the physical parameters characterizing the environment and the system (the thermal bath temperature [Formula: see text], the photons number [Formula: see text], the optomechanical cooperativity [Formula: see text], the squeeze parameter [Formula: see text] and the drive pump power [Formula: see text]). By considering recent experimental parameters, we show that GGD is more robust than entanglement for high thermal bath temperature and low optomechanical cooperativity. We also find that these quantifiers improve with increasing optomechanical cooperativity. The effects of the other parameters are also discussed in detail.

Preparation of hydrophilic modified polyvinylidene fluoride (PVDF) ultrafiltration membranes by polymer/non-solvent co-induced phase separation: effect of coagulation bath temperature

Abstract Membrane separation technology is widely used in wastewater purification, but the issue of membrane fouling could not be ignored. Hydrophilic modification is an effective method to reduce membrane fouling. Therefore, in this work, a hydrophilic modified polyvinylidene fluoride (PVDF) ultrafiltration membrane was prepared by polymer/non-solvent co-induced phase separation, and the effect of coagulation bath temperature on the membrane structure and performance was systematically investigated based on the previous study. With the increased of the coagulation bath temperature, the phase separation process changed from delayed to instantaneous, and the membrane surface changed from porous to dense, while the macropore structures and sponge-like pores appeared on the cross-section. Meanwhile, the pure water flux decreased from 229.3 L/(m2·h) to 2.08 L/(m2·h), the protein rejection rate increased from 83.87% to 100%, and the surface water contact angle increased from 63° to 90°. Thus, excessively high coagulation bath temperature adversely affected the permeate and separation performance, as well as antifouling performance of the membrane. This study enriched the research for preparing separation membranes by polymer/non-solvent co-induced phase separation and provided a practical and theoretical reference for controlling the membrane structure and properties by changing the coagulation bath temperature.

Eruption of the Nyiragongo Volcano on 22 May 2021: Chemical Composition of the "Volcanic Salt" and Collateral Risk

The present study aims to assess the chemical composition of the NaCl-like salt identified on the lava flows of the Nyiragongo volcanic eruption of May 22, 2021, in Kibati not far from the N02 road, in the Bukumu chiefdom; in order to determine its positive or negative impact on the health of the population (for consumers). Samples of these salts are subjected to organoleptic and chemical analysis at the laboratories of the CEEC (Center of Expertise for the Evaluation and Certification of Mineral Substances,) and the OCC in Goma. The results obtained obtained the presence of major elements whose content is greater than 100ppm (mg / kg) and other trace elements whose contents are below 1000ppm, other than certain radioactive elements. These elements come from the magma in a high temperature molten silicate bath, which has given rise to rock (salt) on the surface by rapid cooling of the lava. The high content of silicon and potassium and sodium alkalis clearly shows the alkalinity of the magma of this volcano. It is not in any way the NaCl consumption salt put rather alkalized silica rich in potassium and sodium.

Preparation of hydrophilic polyvinylidene fluoride/polyvinyl alcohol ultrafiltration membrane via polymer/non-solvent co-induced phase separation method towards enhance anti-fouling performance

Membrane separation is a common water treatment technology, but the problem of membrane fouling should not be ignored. Hydrophilic modification is an effective method to reduce membrane fouling. Therefore, PVA/non-solvent co-induced phase separation method was proposed to achieve PVDF ultrafiltration membrane hydrophilic modification and structural control with high concentration polymer coagulation bath. PVA was uniformly distributed on the surface and inside of the hydrophilic modified membrane, which was stable and not easy to leach during filtration. With increasing PVA content in coagulant, the phase separation process changed from instantaneous to delayed, and the membrane surface changed from dense to spherulitic particle accumulation structure, while the connectivity of sponge pores was enhanced until it was completely transformed into a uniform spherical particle structure. The irreversible pollution rates of the modified membrane were 3.28% and 3.48%, respectively, which were significantly lower than those of the unmodified PVDF membranes (25% and 15.26%, respectively) when filtering simulate municipal wastewater with protein and humic acid. The flux recovery rate of the modified PVDF membrane was basically maintained above 90%. This study was a one-step method for membrane structure optimization and hydrophilic modification and contributed a theoretical basis for the role of high concentration polymer coagulant in the membrane forming process.