Production Yield Rate Research Articles

One-step biohydrogen production from cassava pulp using novel enrichment of anaerobic thermophilic bacteria community

The aim of this study is to produce biohydrogen from untreated cassava pulp (CP) using a novel selected consortium of anaerobic thermophilic bacteria and the associated microbial communities were elucidated by metagenomic analysis. CP was chosen as a sole carbon source to enrich efficient hydrogen-producers from a total of 100 different composts and soil sediments under anaerobic dark fermentation at 60 °C. The stable enrichment culture was selected, base on CP degradation and hydrogen production. The selected consortium, namely BK16 from the residue of soil sediment around mangroves at Bangkhuntiean province, Thailand shows the highest hydrogen production yield (35.08 ml H 2 /g substrate) and hydrogen production rate (64.47 mL/day) in one-step. Besides, polysaccharide-degrading enzyme such as amylase, cellulase and xylanase of the BK16 were detected in culture supernatant at 70, 73 and 100 U/mg protein, respectively. In particular, the dominant microbes from selected consortium BK16 comprised of Clostridium thermopalmarium (61.2%) and Clostridium isatidis (25.3%) which have ability to degrade biomass and co-existed with acidogenesis bacteria, belong to the genus Thermoanaerobacterium (6.7%) and Fonticella tunisiensis (5.06%) to produced hydrogen as a consolidate bioprocess (CBP) system. The optimization condition for the hydrogen production of BK16 were at pH 7.0 and 10% (w/v) cassava pulp, in which 760 mL of H 2 /L was produced. Thus, these results revealed that the selected consortia BK16 can be used as an attractive candidate for direct hydrogen production, using cassava pulp as potential raw material for future bio-energy production. • The BK16 has isolated and identified the novel associated microbial communities. • Key biomass-degrading enzyme e.g., amylase, cellulase and xylanase were investigated. • One-step hydrogen production using non-pretreated cassava pulp were optimized.

Homogeneous optimization approach for reducing sensitivity of an optical lens system

During the production of a lens system, the assembling and manufacturing tolerances must be accurately controlled to ensure production efficiency. Thus, it is important to analyze and optimize the tolerance sensitivity of the lens system during the optical design phase to reduce optical performance degradation. We proposed an approach for appropriately controlling the tolerance sensitivity of a lens system. The proposed sensitivity optimization method can homogenize image performance for the same field under different tolerance values. Based on the results, we show that the implementation of the proposed method sharply reduces sensitivity and, consequently, improves the product yield rate by 15 to 17% compared with a traditional optimization method. As a practical example, a 40-megapixel f1.8 mobile phone camera lens design and optimization process was performed in our study. Our preliminary experimental results confirm that the proposed method is effective to reduce the optical sensitivity of the camera lens.

Analysis of earnings forecast of blockchain financial products based on particle swarm optimization

The purpose of this study is to solve the problems of large number of iterations, limitations and poor fitting effect of traditional algorithms in predicting the yield rate of blockchain financial products. In this study, bitcoin yield rate is taken as the research object, and data from June 2, 2016 to December 30, 2018 are collected, totaling 943 pieces. The BP neural network, support vector regression machine algorithm and particle swarm optimization least square vector algorithm are respectively adopted to carry out model simulation and empirical analysis on the collected data, and it is concluded that particle swarm optimization least square vector algorithm has the best fitting effect. Subsequently, the Ethereum (ETH) yield rate is selected as the research object, and the model simulation and empirical analysis are carried out on it, which verifies that the optimized algorithm has better prediction and fitting on the time series. The results show that the particle swarm optimization algorithm among the three algorithms mentioned in this research has the best prediction effect. Therefore, the results of this study have a good fitting effect on the prediction of the yield rate of blockchain financial products, have a good guiding effect on the investors of blockchain financial products, and have a good guiding significance for the study of the yield rate of China’s blockchain financial products.

Motion estimation-based inclination measurement of industrial assembly platform

This paper presents a method for measuring the inclination angle of bearing mounting plane based on binocular vision technology. In the actual installation process of the bearing, the mounting plane will have a certain degree of inclination. To improve the product yield rate, this paper designs the inclination measurement system by using binocular vision technology and the proposed optimised perspective-n-point (PnP) method. After experimental testing, the measurement system for inclination angle proposed in this paper can meet the requirements of the production process. The proposed approach achieves high measurement accuracy as well as good real-time performance.

(t,n): Sensor Stipulation with THAM Index for Smart Agriculture Decision-Making IoT System

The rapid growth of industrial infrastructure creates ecological issues such as climate change. Field indecisiveness affects agricultural yields due to improper measurement, field assessment, selection of sensors and deployment of sensors. The accurate prediction of changes in weather parameters, field assessment and soil parameters, has become an outstanding challenge for the agricultural IoT. To solve this problem, we propose a (t, n) sensor selection mechanism and a soil temperature, humidity, air- and water-quality measurement (THAM) index for node stipulation, based on a smart decision-making system for the agricultural domain that considers the temperature quotient, an NPK fertilizer regulatory model and the agronomy function. The (t, n) node stipulation index defines an optimal number of sensors to monitor the field. The temperature quotient considers soil temperature and moisture to assess the growth rate. The agronomy function, based on water pH level and SO$${_2}$$ concentration level in air, assesses the production yield rate of the field. This framework improves the prediction performance for detecting abnormal conditions by 75%, with a reduction in the creation of unimportant data and the resources loss rate. It increases the agricultural production yield compared to existing systems.

Study of Light Wavelength Dependency in Red-Orange Spectrum on Continuous Culture of Synechocystis sp. PCC6803

In this study, the effect of light wavelength on growth rate and lipid production of Synechocystis was investigated. Continuous cultivation system was used to have uniform cell density and avoid self-shading in order to obtain more precise results. Based on previous studies, red light is more efficient than other colors in the visible spectrum for cultivation of Synechocystis; however, the optimum wavelength in red light spectrum remains still unknown. In order to determine the most efficient wavelength of red light, five different wavelengths including 600, 635, 660, 670, and 730 nm were used for growing Synechocystis in a chemostat setup. The results revealed that 635 nm was the most efficient wavelength for cultivation of Synechocystis in terms of both biomass production yield and growth rate. These findings can be attributed to the existence of phycocyanin, the principal light-harvesting supercomplex in Synechocystis, which absorbs maximally at around 620 nm. The results also indicated that cell size and fatty acid profile of Synechocystis were almost the same for different light wavelengths; however, the maximum light was absorbed at 635 nm.

Boosting Electrochemical Nitrogen Reduction Performance over Binuclear Mo Atoms on N-Doped Nanoporous Graphene: A Theoretical Investigation.

Exploration of efficient catalysts is a priority for the electrochemical nitrogen reduction reaction (NRR) in order to receive a high product yield rate and faradaic efficiency of NH3, under ambient conditions. In the present contribution, the binding free energy of N2, NNH, and NH2 were used as descriptors to screen the potential NRR electrocatalyst among different single or binuclear transition metal atoms on N-doped nanoporous graphene. Results showed that the binuclear Mo catalyst might exhibit the highest catalytic activity. Further free energy profiles confirmed that binuclear Mo catalysts possess the lowest potential determining step (hydrogenation of NH2* to NH3). The improved activities could be ascribed to a down-shift of the density of states for Mo atoms. This investigation could contribute to the design of a highly active NRR electrocatalyst.

Pricing and ordering decisions in a supply chain with downward substitution and imperfect process yield

We consider a manufacturer sourcing from two suppliers of asymmetric component quality and producing a quality-differentiated product, namely a low- and high-quality version, with each having deterministic demand. The manufacturer adopts the existing process to produce low-quality products with components from the supplier with low component quality, and develops a new process to produce high-quality products with components from the supplier with high component quality. The new process has imperfect yield, and products that do not meet the specifications for high-quality products can substitute for low-quality products produced with the existing process. We investigate the suppliers’ price decisions and the manufacturer’s ordering and production decisions in a game-theoretical model under dual sourcing. Our analyses reveal that increasing product differentiation or higher yield of high-quality products do not necessarily translate to a higher profit for the manufacturer. In light of the manufacturer’s sourcing strategies, we show that sourcing from a single supplier with high- and low-quality components yields a lower profit than sourcing from one supplier with high component quality and the other with low component quality. Finally, we investigate the manufacturer’s decision-making with endogenous yield rate of high-quality products. Our analyses demonstrate that the manufacturer benefits from setting the yield rate of high-quality products ahead of the suppliers’ price decisions.

Bimodal nanoporous Pd3Cu1 alloy with restrained hydrogen evolution for stable and high yield electrochemical nitrogen reduction

Electrocatalytic nitrogen reduction reaction (NRR) under ambient temperature and pressure holds a great promise for NH3 production while it is still impeded by the low active site density and sluggish kinetics, leading to a low product yield rate. In this work, bimodal nanoporous PdCu alloys that have three-dimensional hierarchical interconnected porous network and tailored Pd/Cu atomic ratios are designed and used for electrocatalytic NRR with high NH3 yield rate at room temperature and atmosphere pressure. The Pd3Cu1 alloy that has large surface area for high active site density, bimodal porous structure for efficient reactant accessibility as well as desired electronic structure for restrained hydrogen evolution reaction exhibits a high NH3 yield rate of 39.9 μg h−1 mgcat−1, which is among the highest values for recently reported NRR electrocatalysts with high loading amount. Even at a low overpotential of − 0.15 V versus reversible hydrogen electrode (vs RHE), the alloy can still deliver a NRR yield rate of more than 10 μg h−1 mgcat−1. Moreover, structural integrity of the Pd3Cu1 alloy makes it a highly stable NRR electrocatalyst that keeps 100% of its original activity after 18 h operation, retaining its great potential for promising NRR electrocatalysis. The synergistic combination of bimodal nanoporous structure and alloy strategy could be used to design efficient catalysts for a wide range of reactions.

Effect of triclocarban on hydrogen production from dark fermentation of waste activated sludge

This work aims to investigate whether and how TCC affects hydrogen production using both experimental and model approaches. Experimental results showed that the exposure of TCC not only enhanced the hydrogen production yield but also promoted the hydrogen yield potential and hydrogen production rate. The maximum hydrogen production yield and hydrogen production rate increased from 10.1 ± 0.2 to 14.2 ± 0.2 mL/g VSS and 0.09 to 0.13 mL/g VSS·h, respectively, when TCC level increased from 0 to 1403 ± 150 mg/kg TSS. Mechanism exploration showed that the presence of TCC significantly promoted the release of substances and observably facilitated the acidification process but seriously inhibited the methonogenesis and homoacetogenesis processes. Further investigations with enzyme analysis revealed that TCC importantly increased the activities of acetate kinase and [FeFe] hydrogenase but seriously inhibited the activities of carbon monoxide dehydrogenase and Coenzyme F420.

Consequences of Heterogeneous Crowding on an Enzymatic Reaction: A Residence Time Monte Carlo Approach.

Translational diffusion of a free substrate in crowded metabolically active spaces such as cell cytoplasm or mitochondrial matrix is punctuated by collisions and nonspecific interactions with soluble/immobile macromolecules/macrostructures in a variety of shapes/sizes. It is not understood how such disruptions alter enzyme reaction kinetics in such spaces. A novel Monte Carlo (MC) technique, “residence time MC”, has been developed to study the kinetics of a simple enzyme–substrate reaction in a crowded milieu using a single immobile enzyme in the midst of diffusing substrates and products. The reaction time lost while the substrate nonspecifically interacts or is transiently trapped with ambient macromolecules is quantified by introducing the residence time “tau”. Tau scales with the size of crowding macromolecules but makes the knowledge of their shape redundant. The residence time thus presents a convenient parameter to realistically mimic the sticky surroundings encountered by a diffusing substrate in heterogeneously crowded physiological spaces. Results reveal that for identical substrate concentration and excluded volume, increase in tau significantly diminished enzymatic product yield and reaction rate, slowed down substrate/product diffusion, and prolonged their relaxation times. A smooth transition from the anomalous subdiffusive motion to normal diffusion at long time limits was observed irrespective of the value of tau. The predictions from the model are shown to be in qualitative agreement with in vitro experimental data revealing the rate of alkaline phosphatase-catalyzed hydrolysis of p-nitrophenyl phosphate in the midst of 40/500/2000 kDa dextrans. Our findings from the residence time MC model also attempt to rationalize previously unexplained experimental observations in crowded enzyme kinetics literature. Furthermore, major insights to emerge from this study are the reasons why free diffusion of the substrate in crowded physiological spaces is detrimental to enzyme function. It is argued that organized enzyme clusters such as “metabolon” may perhaps exist to regulate the substrate translocation in such sticky physiological spaces to maintain optimal enzyme function. In summary, this work provides key insights explaining why absence of substrate channeling can dramatically slow down enzyme reaction rate in crowded metabolically active spaces.

Enrichment of chalcopyrite using high-voltage pulse discharge

In this study, high-voltage pulse was used for crushing copper ore. The effects of operational parameters on product size, yield and enrichment rate were studied. The influence of operational parameters on the yield of unit energy consumption (δ) for crushing was investigated using orthogonal experiments. The results showed that the variation trend in the content of completely broken product was opposite to that of the average grain size. The rate of enrichment (β) of chalcopyrite first increased, and then, decreased with the increase in voltage. However, the rate of enrichment decreased with the increase in the number of pulses, and was less affected by the spacing between the electrodes. With the continuous change in operational parameters, β for the chalcopyrite gradually stabilized within the range of 1.1–1.2. The high-voltage pulse can effectively enrich chalcopyrite, while the overall variation trend of β showed a decline with the increase in grain size. However, the value of β was higher than unity. Furthermore, the value of β for −0.3 mm broken product was relatively higher, and was about 1.46. Except for the 0.3 mm and 4 mm size fractions, there was no obvious turning point in the β curve of other size fractions. Additionally, the effect of size fraction on the value of β was weak. Under the conditions of breaking the mineral, the voltage had the greatest influence on δ value, which increased with the decrease of voltage and number of pulses. At 110 kV and 55 number of pulses, the maximum value of δ was up to 1.66, which gradually declined in the direction of increasing energy consumption.

Silica–Carbon Nanocomposite Acid Catalyst with Large Mesopore Interconnectivity by Vapor-Phase Assisted Hydrothermal Treatment

Mesostructured silica–carbon nanocomposites with large mesopore interconnectivity are created from sucrose as sustainable carbon source using a mild vapor-phase assisted hydrothermal treatment procedure. The resultant mesostructured silica–carbon nanocomposite can be readily sulfonated to provide a strong acid catalyst with high sulfonic acid density, or the carbon phases of the nanocomposite can be removed by calcination to produce a silica material with ultrahigh porosity (Vpore = 1.25 to 1.34 cm3 g–1). A superior catalytic activity is demonstrated for the solvent-less condensation of 2-methylfuran with furfural; both product yield and conversion rate surpass that of reference catalysts such as their counterparts from dry pyrolysis and the commercial strong acid resins. The enhanced catalytic activity is attributed to the higher SO3H acid density (0.64 to 1.08 mmol g–1), the larger and better communicating mesopores (Vmeso = 0.38 to 0.82 cm3 g–1) and the abundant presence of surface oxygen-containing fu...

Improved vaginal retention and enhanced antifungal activity of miconazole microsponges gel: Formulation development and in vivo therapeutic efficacy in rats

Traditional azole antifungal formulations suffer from poor retention in the vaginal cavity, irritation and burning of the vaginal area. In the present work, we aim at the development of a novel miconazole (MCZ) microsponges gel as an attractive dosage form for vaginal candidiasis. The proposed formula has the potential to minimize the local side effects of the drug due to the controlled release characteristic, which increases patient compliance. Moreover, the mucosal retention effect of the microsponges in addition to the bioadhesion property of Carbopol gel prolongs the retention of the dosage form in the vagina and consequently improves the therapeutic efficiency. MCZ microsponges were prepared applying Quasi emulsion method using Eudragit RS100. The effect of formulation factors, namely, drug:polymer ratio (1:1, 2:1 and 4:1), the amount of poly vinyl alcohol (PVA) (25, 50 and 75mg) and the volume of organic solvent (2.5, 5, 10mL) on the characteristics of MCZ microsponges has been investigated. The microsponges were optimized regarding the production yield (68.8±6.4%), particle size (78.2±2.1μm), entrapment efficiency (92.9±1.9%) and release rate (Q150 51.8±2.5%). The selected formula was further evaluated for its, flowability, porosity and surface morphology. MCZ microsponges were incorporated into Carbopol gel, then the viscosity and bioadhesion were examined. The in vitro antifungal activity of MCZ microsponges gel was comparable to the market product. In vivo, MCZ microsponges vaginal gel was more effective than the market product (p<0.05) in eradicating Candida infection in rats, which was supported by the histopathological findings.

High throughput, continuous, solvent-free synthesis of ionic liquid [BMIM]Br in a microbore tube

A microbore tube is used to synthesize an imidazolium-based ionic liquid 1-butyl-3-methylimidazolium bromide ([BMIM]Br) in continuous and solvent-free mode to achieve high space-time-yield and production rate while ensuring operation in kinetically controlled regime. Within the range of the experiments, product yield is found to increase with an increase in reaction temperature and residence time. Maximum values of space-time-yield and production rate achieved are 216gm/min-L and 1172gm/day, respectively. The effects of different parameters (design of the microfluidic junction, flow velocity, and the extent of coiling of the microbore tube) on the product yield and production rate are studied. Opposed T-junction is found to be better than cross T-junction. Product yield increases when flow velocity is increased keeping the residence time unchanged. Product yield is found to increase with reduction in coiling diameter. Though the use of a microbore tube ensures kinetically controlled regime, a few experiments are deliberately carried out in mass transfer controlled regime to understand the issues that become important in mass transfer controlled regime.

Simulation of thin film thickness distribution for thermal evaporation process using a scanning linear source

Thermal evaporation process is the main process involved in the production of OLED displays and with the trends toward larger substrate size and display resolution, film thickness uniformity must be carefully controlled in order to implement exact pixel data. To secure stable film thickness uniformity on the substrate area, thin films are deposited on large-area glass substrates via thermal evaporation process using a linear source. We designed a linear source and mathematical model was developed to describe the system with a focus on the linear source. Then, system parameters were determined to guarantee uniform thickness using computer-based simulation, replacing wasteful actual experiments, followed by carrying out experiments based on the determined parameters. After the deposition process, data from the mathematical model and experiments was compared and the resulting agreement was good, verifying the validity of the proposed method. Consequently, by applying the proposed method, display manufacturing process related to thermal evaporation can be controlled within a tight tolerance in order to maximize the production yield rate.

Towards More Efficient, Greener Syntheses through Flow Chemistry.

Technological advances have an important role in the design of greener synthetic processes. In this Personal Account, we describe a wide range of thermal, photochemical, catalytic, and biphasic chemical transformations examined by our group. Each of these demonstrate how the merits of a continuous flow synthesis platform can align with some of the goals put forth by the Twelve Principles of Green Chemistry. In particular, we illustrate the potential for improved reaction efficiency in terms of atom economy, product yield and reaction rates, the ability to design synthetic process with chemical and solvent waste reduction in mind as well as highlight the benefits of the real-time monitoring capabilities in flow for highly controlled synthetic output.

Finite element analysis and experimental study on electrical damage of silicon photodiode induced by millisecond pulse laser

In this paper, based on the thermal elasto-plastic constitutive theory and the equivalent specific heat method, the electrical damage in the silicon-based positive-intrinsic-negative (PIN) photodiode irradiated by millisecond (ms)-pulsed laser is investigated. On condition that the internal material of the photodiode is isotropic and threelayer structure of the P-I-N satisfying temperature continuity and heat flow balance, a two-dimensional (2D) simulation axisymmetric model for silicon-based PIN photodiode irradiated by ms-pulsed laser is built. The thermal and stress field distribution are simulated in the silicon-based PIN photodiode irradiated by the Nd:YAG ms-pulsed laser at 1064 nm through using the finite element simulation software. At the same time, electrical parameters before and after the experiment of the silicon-based PIN photodiode irradiated by pulsed laser are measured. The experimental results show that the surface is melted and ablated gradually with the increase of temperature in the high energy pulsed laser, and there is a gradient change for the temperature in spatial distribution. With the increase of laser energy density, photoelectric detector shows the temperature rise phenomenon and damage effect is more obvious. When the tensile stress or compressive stress is greater than 1.7 GPa, the photosensitive surface and the silicon lattice are damaged with the changes of thermal and stress fields. Bond cleavage can change the photogenerated carrier transport channel, and the transport time can be longer. In this process, the photogenerated electron-hole pairs are readily recombined, carrier lifetime decrease and carrier concentration increase, which leads to the increase of the dark current and the decrease of the responsivity. Eventually the performance of photodetector detection is reduced. Through comprehensive comparison between experiment and simulation, one can confirm that this theoretical model has a considerable level of reliability. The conclusion we can draw is that the threshold of electrical damage is 1.7 GPa. So the control of annealing temperature is extremely important for the process of making PIN photodiode. Preventing the lattice damage of the material can improve the product yield rate. In addition, from the point of view of the use of products, the stability of the working environment can extend the service life of products, and the detection accuracy is guaranteed. Conclusively, the results in this paper establish the foundation to investigate the electrical damage mechanism in the silicon-based PIN photodiode irradiated by ms-pulsed laser.

Treatment of high-strength ethylene glycol waste water in an expanded granular sludge blanket reactor: use of PVA-gel beads as a biocarrier.

Industrial-scale use of polyvinyl alcohol (PVA)-gel beads as biocarriers is still not being implemented due to the lack of understanding regarding the optimal operational parameters. In this study, the parameters for organic loading rate (OLR), alkalinity, recycle rate, and addition of trace elements were investigated in an expanded granular sludge blanket reactor (EGSB) treating high-strength ethylene glycol wastewater (EG) with PVA-gel beads as biocarrier. Stable chemical oxygen demand (COD) removal efficiencies of 95 % or greater were achieved, and continuous treatment was demonstrated with appropriate parameters being an OLR of 15 kg COD/m3/day, NaHCO3 added at 400 mg/L, a recycle rate of 15 L/h, and no addition of trace elements addition. A biogas production yield rate of 0.24 m3/kg COD was achieved in this study. A large number of long rod-shaped bacteria (Methanosaeta), were found with low acetate concentration in the EGSB reactor.

A study on warpage behavior of EMC in post-mold cure stage using Moldex3D

Warpage and residual stress are the two most important factors affecting product yield rate and reliability in IC encapsulation process. This study presents the prediction of warpage in post-mold cure stage using a three-dimensional finite element approach coupled with linear viscoelastic material property. Furthermore, cure-induced volumetric shrinkage and thermal expansion mismatch are considered. The shrinkage of the EMC is described by Pressure-Volume-Temperature-Cure (PVTC) model, and Generalized Maxwell model; WLF relation is adopted to describe the viscoelastic behavior of EMC. In order to obtain accurate numerical results, Cure-Time-Temperature superposition is considered. For verifying the numerical predictions of three dimensional simulations, the calculated results are compared with the available experimental data from literature.