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Influence of Substrate Feeding and Process Parameters on Production of Coenzyme Q<sub>10</sub>Using <i>Paracoccus denitrificans</i>ATCC 19367 Mutant Strain P-87 被引量:1
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作者 Pradipta Tokdar Prafull Ranadive +2 位作者 Rajendra Kshirsagar Samanta Shekhar Khora Sunil Kumar Deshmukh 《Advances in Bioscience and Biotechnology》 2014年第12期966-977,共12页
Coenzyme Q10 (CoQ10), an important antioxidant molecule playing a major role in electron transport chain, has been commercially produced by fermentation process for the use in oral nutraceutical formulations. Construc... Coenzyme Q10 (CoQ10), an important antioxidant molecule playing a major role in electron transport chain, has been commercially produced by fermentation process for the use in oral nutraceutical formulations. Constructing the high-yielding CoQ10 producing strains is a pre-requisite for cost-effective production. A superior mutant strain P-87 generated from Paracoccus denitrificans ATCC 19367, which showed 1.25-fold improvement in specific CoQ10 content higher than the wild type strain at shake flask level, was selected to carry out the studies on CoQ10 yield improvement through fermenter process optimization. In the course of study, initially the cane-molasses-based medium and fed-batch fermentation strategy using pHBA in combination with sucrose were standardized in shake flask using wild type strain. This strategy was subsequently translated at 2 L laboratory fermenter while optimizing the fermentation process parameters using improved mutant strain P-87. Under optimized fermentation condition, mutant strain P-87 produced 49.85 mg/L of CoQ10 having specific content of 1.63 mg/g of DCW, which was 1.36 folds higher than the specific CoQ10 content of wild-type strain under similar optimized condition. The temperature and DO were found to be critical parameters for CoQ10 production by mutant strain P-87. The optimum temperature was found to be 32°C and the optimum DO concentration to be maintained throughout the fermentation cycle was found to be 30% of air saturation. Overall, a new cost-effective process has been established for the production of CoQ10 using the cheaper substrate “cane molasses” and higher CoQ10 producing mutant strain P-87. 展开更多
关键词 CoQ10 PARACOCCUS DENITRIFICANS Cane MOLASSES pHBA Sucrose DO Process Optimization
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Integrating species and successional classes for wood production in a mixed forest restoration system in a neotropical region 被引量:1
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作者 Ananias Francisco Dias Junior Ana Lucia Martins Sodero Pincelli +4 位作者 Ana Paula Camara da Silva Alison Moreira da Silva Natalia Dias de Souza Mario Tommasiello Filho Jose Otavio Brito 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第6期2313-2321,共9页
As forests in neotropical regions,particularly in developing countries,are devastated,interventions to restore biodiversity and its ecological functions are needed.Rural producers have thus been encouraged to grow tre... As forests in neotropical regions,particularly in developing countries,are devastated,interventions to restore biodiversity and its ecological functions are needed.Rural producers have thus been encouraged to grow trees for wood production as an economic activity.The objective of this study was to quantify the increment of wood density of four forest species from different successional classes of a mixed system of restoration in a neotropical forest in Brazil.Tree discs were sampled at breast height and analyzed radially by X-ray densitometry to obtain apparent density and basic density.Three trees each of a species from the pioneer,early and late secondary successional stages and of the dominant species in the climax community.The radial profiles indicated increasing density from the pith to bark of trunks,except for some variations due to wood defects and growth.Average density was 0.576 g cm^(-3),0.655 g cm^(-3),0.706 g cm^(-3)and 0.775 g cm^(-3),respectively,for Peltophorum dubium,Schinus terebinthifolius,Cariniana estrellensis and Hymenaea courbaril.Radial profiles indicated higher amplitudes in the apparent densities for slow-growing species.X-ray densitometry generated parameters such as minimum,average and maximum densities,and radial density variations.These parameters are important for understanding the ecological functional role of successional classes of the Atlantic Forest from the Neotropical region. 展开更多
关键词 X-ray densitometry Timber species of neotropical forest Successional classes of forest species Maintenance of forest restoration
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Effect of Organic Fertilizer Doses on the Plant Growth,Essential Oil Production and Chemical Substances of "Carqueja" over Two Harvest Moments 被引量:1
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作者 Daniel Garcia Paulo Sérgio Siberti da Silva +3 位作者 Marcos Roberto Furlan Monica Tiho Chisaki Isobe Marcia Ortiz May Marques Lin Chau Ming 《Journal of Agricultural Science and Technology(B)》 2017年第2期114-124,共11页
This study aimed to investigate, for the first time, the plant growth, essential oil content and their chemical substances ofBaccharis trimera (Less.) DC., the first Brazilian variety of medicinal plant, in response... This study aimed to investigate, for the first time, the plant growth, essential oil content and their chemical substances ofBaccharis trimera (Less.) DC., the first Brazilian variety of medicinal plant, in response to five doses of organic fertilizer (0, 10, 20,30, 40 and 50 ton/ha) over two harvest moments-120 d and 242 d after transplanting (DAT). The work was carried out fromFebruary to October 2011 at the experimental farm of the Sao Paulo State University "Julio de Mesquita Filho" (UNESP), Brazil.The seedlings of B. trimera var. CPQBA-1 were respectively transplanted into experiment plots under six treatments: 0, 10, 20, 30,40 and 50 ton/ha of organic fertilizer. Each treatment had four replications and each plot consisted of 12 plants. Then they wereharvested at 120 DAT and 242 DAT, and the essential oil were extracted by hydrodistillation and analyzed by gas chromatograph.The results were subjected to analysis of variance and the means were analysed using Tukey's test (5%) followed by a regressionanalysis. The fertilizer dose significantly influenced the height of the plants in the second harvest, while the higher dose of organicfertilizer positively impacted the essential oil content in the first harvest. Also, the level of organic fertilizer was directly correlatedwith the production of dry matter during the regrowth. Twenty-seven substances were identified in the essential oil samples, and themajor components were: bicyclogermacrene, trans-caryophyllene, germacrene-D, spathulenol and caryophyllene oxide. Thesefindings suggest that to obtain higher yields of dry matter ofB. trimera, it should be harvested around 242 DAT and organic fertilizershould be applied approximately to 50 ton/ha. Furthermore, higher doses of organic fertilizer and harvest at 120 DAT is able toincrease the essential oil content. 展开更多
关键词 BACCHARIS trimera BRAZILIAN MEDICINAL plant dry matter CHEMICAL substances bicyclogermacrene.
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Effect of Stocking Density on Growth Performance, Production Trait, Food Utilization and Body Composition, of Meagre (Argyrosomus regius)
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作者 A. Ghozlan M. A. Zaki +3 位作者 M. A. Essa M. M. Gaber E. H. Ebiary A. Nour 《World Journal of Engineering and Technology》 2018年第3期37-47,共11页
A 10-week rearing trial was conducted in cages with average initial weight of 9.15 ± 0.2 g/fish and average initial length of 9.2 ± 0.02 cm/fish of meagre, Argyrosomus regius, to examine the effect of three ... A 10-week rearing trial was conducted in cages with average initial weight of 9.15 ± 0.2 g/fish and average initial length of 9.2 ± 0.02 cm/fish of meagre, Argyrosomus regius, to examine the effect of three stocking density on growth performances, production traits, feed utilization and body composition. Nine cages 24 m3 each (4 × 6 × 1.5 m, long, width and height) were stocked with either 1200, 3600 and 6000 fish for each cage to give a stocking rate of 50, 150, and 250 fish/m3 respectively and fish fed daily, slightly in excess of satiation to eliminate the possibility of food supply being a limiting factor to growth. The results revealed that, mean final weight (g/fish), gain in weight, SGR (%per day), feed conversion ratio, protein efficiency ratio and total feed intake (g/fish) were significantly (P ≤ 0.01) influenced. The best at the lowest stocking density, while, the total production and net production exhibited significantly the opposite trend. Harvest and production estimates increased with increasing stocking density. Fish body composition% of moisture, protein, fat and ash were significantly (P ≤ 0.01) influenced by stocking density. From the above results and the economic information of the study, it can be concluded that stocking density of 50 fish/m3 of meagre exhibited the highest net profit and would seem to be the most desirable density in the system studied. 展开更多
关键词 STOCKING Density Meagre Growth PRODUCTION BODY COMPOSITION
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Geothermal Energy Production Potential from Oil and Gas Fields in Western Ukraine
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作者 Oleksandr Burachok Oleksandr Kondrat 《Journal of Geological Resource and Engineering》 2019年第4期123-131,共9页
Western Ukraine as well as Crimea Peninsula is well known for their geothermal potential.The classic low enthalpy geothermal project is based on the construction of a binary power plant,and includes recycling of water... Western Ukraine as well as Crimea Peninsula is well known for their geothermal potential.The classic low enthalpy geothermal project is based on the construction of a binary power plant,and includes recycling of water through one or several doublets of wells;produced hot water is directed to a heat exchanger(vaporizer),in which a secondary(working)fluid with low boiling point and high vapor pressure vaporizes and rotates a turbine to produce electricity.The highest risk for the project is associated with drilling new wells,which may not hit the target or not have the required productivity.Western Ukraine is one of the oldest oil and gas production regions in Europe.The majority of the fields are on a late stage of the development that is characterized with high produced volumes of water that after separation is being reinjected back for pressure support.In this study,we evaluated the possibility of geothermal energy production,extracted from water that is produced together with oil and gas,based on numerical reservoir simulation models for a typical reservoir setting. 展开更多
关键词 WESTERN Ukraine GEOTHERMAL ENERGY ENERGY PRODUCTION POTENTIAL sensitivity analysis RESERVOIR simulation
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Study on the Effect of Production Parameters and Raw Materials Used on the Mechanical Properties of Leaded Brass (CuZn40Pb2) Alloy
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作者 Abdulsalam A. Fadhil Tawakol A. Enab +2 位作者 Magdy Samuel Berlanty A. Iskander Sami A. Ajeel 《World Journal of Engineering and Technology》 2017年第2期340-349,共10页
Leaded brass alloys used progressively in many applications such as gas valves production owing to their excellent machinability, corrosion resistance and some other specifications. However, the production processes o... Leaded brass alloys used progressively in many applications such as gas valves production owing to their excellent machinability, corrosion resistance and some other specifications. However, the production processes of these alloys involve some problems appearing in the last activities of production as a result of cumulative defects of previous production processes. Therefore, the current investigation studies the effect of process parameters during casting, hot extrusion and cold drawing production stages of CuZn40Pb2 leaded brass alloy on the mechanical properties. Starting with casting process, two types of charges were used. The first charge consists of 100% recycles while the second contains 30% of pure materials such as Cu, Zn and Pb in addition to the recycles. For each production stage, alloy hardness, micro-hardness, ultimate tensile strength and elongation were examined. The results illustrated that high hardness values are obtained during casting process due to some impurities such as iron and the effect of cooling rate through solidification. The hardness values decrease during extrusion process and then rise again by cold drawing for the charge of 30% pure materials. Micro-hardness values for the fractured tensile test samples appeared higher than others due to work hardening effect. The best mechanical properties as ultimate tensile strength of CuZn40Pb2 alloy products are appeared into cold forming samples with the 30% pure material added. 展开更多
关键词 Leaded BRASS ALLOY MECHANICAL Properties HARDNESS Work HARDENING
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Multi-Objective Production Planning Using Lexicographic Procedure
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作者 Mohamad Sayed Al-Ashhab Taiser Attia Shadi Mohammad Munshi 《American Journal of Operations Research》 2017年第3期174-186,共13页
This paper presents a multi-objective production planning model for a factory operating under a multi-product, and multi-period environment using the lexicographic (pre-emptive) procedure. The model objectives are to ... This paper presents a multi-objective production planning model for a factory operating under a multi-product, and multi-period environment using the lexicographic (pre-emptive) procedure. The model objectives are to maximize the profit, minimize the total cost, and maximize the Overall Service Level (OSL) of the customers. The system consists of three potential suppliers that serve the factory to serve three customers/distributors. The performance of the developed model is illustrated using a verification example. Discussion of the results proved the efficacy of the model. Also, the effect of the deviation percentages on the different objectives is discussed. 展开更多
关键词 MULTI-OBJECTIVE Production PLANNING GOAL PROGRAMMING Multi-Products and Multi-Periods
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Modeling of Tuna Fish Frying Using Response Surface Methodology in the Production of Attieke “Garba” Dish in Côte D’Ivoire
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作者 Daouda Nimaga Massogbe Diabate +4 位作者 Nestor Kouakou Kouassi Elisée Yapi Kouakoua Charlemagne Nindjin Joseph Dossou Georges N’Guessan Amani 《Food and Nutrition Sciences》 CAS 2024年第10期959-973,共15页
With the aim of optimizing the factors which act on the frying of the fish dish “Garba”, a study using the response surface methodology was carried out. After an appropriate choice of three variables, 15 experiments... With the aim of optimizing the factors which act on the frying of the fish dish “Garba”, a study using the response surface methodology was carried out. After an appropriate choice of three variables, 15 experiments led to three second-order mathematical models linking the responses (temperature, number of reuses, frying time) to the factors and allowing good control of the frying process. After carrying out the tests and analyzing the data, the study provided knowledge of the optimal conditions necessary for frying while preserving the quality of the oil. The optimal point region for maintaining this quality is obtained when the temperature is 160˚C at frying times of 7.5 minutes for only 5 reuses of the oil. 展开更多
关键词 Attieke FRYING Optimization Surface Plan
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Life-Cycle Impact Assessment of Air Emissions from a Cement Production Plant in Cambodia
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作者 Chanto Chea Pinnara Ket +6 位作者 Long Taing Sela Kong Dalin Um Chanreaksmey Taing Chanmoly Or Srean Aun Leakhena Hang 《Open Journal of Air Pollution》 CAS 2022年第4期85-99,共15页
Cement industrial emissions account for 32% of air pollution in Cambodia. With that in mind, we examined the environmental impact of Cambodia’s cement industry and identified ways that it could reduce air pollution. ... Cement industrial emissions account for 32% of air pollution in Cambodia. With that in mind, we examined the environmental impact of Cambodia’s cement industry and identified ways that it could reduce air pollution. The study focused on raw material extraction and preparation, calcination, and cement preparation. Data for the life-cycle inventory were provided by the Kampot Cement Plant. Air emissions were assessed using EMEP/EEA and IPCC criteria, and the impact assessment used ReCiPe (2016). The baseline analysis revealed that calcination contributed the most air pollutants, so mitigation scenarios focused on alternative fuels only during the calcination stage of cement production: 1) 100% coal (S1);2) 93% coal and 7% biomass (S2);3) 85% coal and 15% biomass (S3);4) 70% coal and 30% biomass (S4);and 5) 50% coal and 50% biomass (S5). The results demonstrated that certain mitigation measures reduced major emissions and environmental damage. S5 had the best results, reducing CO<sub>2</sub> by 49.97, NOx by 2.233, and SO<sub>2</sub> by 49.333%;however, it increased PM<sub>2.5</sub> by 19.60% and total heavy metal (Pb, Cd, Hg, As, Cr, Cu, Ni, Se, Zn) output by 28.113%. The results of the study showed reductions in serious health and environmental effects associated with climate change of 48.83%, ozone generation of 9.62%, and particulate matter formation of 28.80%. However, carcinogenic and non-carcinogenic human toxicity increased by 35.66%. Therefore, such mitigation effect would be benefit to carbon reduction target in Cambodia. 展开更多
关键词 Biomass CEMENT CLINKER Environmental Impacts European Monitoring and Evaluation Program Life Cycle Impact Assessment Midpoint Impact Endpoint Impact
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Production Well Microbial Mitigation and H2S Risk Management
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作者 Abdulmohsen Al-Humam Hisham Al-Shuwaikhat +2 位作者 Bahkly Thamer Abdullah Al-Nami Salman Al-Ramel 《Journal of Physical Science and Application》 2020年第2期19-29,共11页
One Field has been eternally acknowledged as a sweet arena without the presence of any souring phenomena.On the other hand,the Sulfate Reducing Bacteria(SRB)growth which has been lately observed in the field Water Inj... One Field has been eternally acknowledged as a sweet arena without the presence of any souring phenomena.On the other hand,the Sulfate Reducing Bacteria(SRB)growth which has been lately observed in the field Water Injection System played a major role in increasing the H2S concentrations in particular A fields.The objective of this study is to mitigate the SRB growth in the A Water Injection System and manage the risk of the Hydrogen Sulfide(H2S).In order to reduce the H2S concentrations and the return the Fields back to their original states.Thereafter,Biocide Treatment usage;based on the thorough evaluation performed in both the Lab and Fields by collecting more than 100 samples from designated wellheads and identified sampling points in the field Water Injection System network.Biocide field trial for one year was conducted with a persistent monitoring program.It appealed that the Biocide Treatment is influential,efficient and functional,carving deeper in the SRB mitigation and H2S risk management,the averaged H2S concentrations and trends in the Fields are being controlled and minimized in both the oil and gas phases. 展开更多
关键词 H2S risk management SRB mitigation
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Lot Sizing in Production Scheduling at a Personal Protection Equipment Company
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作者 José Roberto Dale Luche Rodolfo Egon Perhs 《American Journal of Operations Research》 2016年第5期378-386,共10页
This work presents an optimization model to support decisions during production planning and control in the personal protective equipment (PPE) industry (in particular, gloves). A case study was carried out at a Brazi... This work presents an optimization model to support decisions during production planning and control in the personal protective equipment (PPE) industry (in particular, gloves). A case study was carried out at a Brazilian company with the aim of increasing productivity and improving customer service with respect to meeting deadlines. In this case study, the mixed integer linear programming model of Luche (2009) was revisited. A new model for single-stage lot sizing was applied to the production scheduling of gloves. Optimizing this scheduling was not a simple task because of the scale of the equipment setup time, the diversity of the products and the deadlines for the orders. The model was implemented in GAMS IDE and solved by CPLEX 12. The model and the associated heuristic produce better solutions than those currently used by the company. 展开更多
关键词 Lot Sizing Production Planning Personal Protective Equipment
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Management Practice of Nuclear Power Production Preparation Plan
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作者 SUN Shibo 《外文科技期刊数据库(文摘版)工程技术》 2021年第5期065-067,共5页
With the rapid development of economy and the continuous progress of science and technology, the development of China's nuclear power industry has also made remarkable achievements. Today, with the continuous impr... With the rapid development of economy and the continuous progress of science and technology, the development of China's nuclear power industry has also made remarkable achievements. Today, with the continuous improvement of the market economy system, the old nuclear power production plan management system cannot meet the market demand and the demand of various industries. For the safe operation of enterprises, nuclear power production provides an important basic guarantee. In view of this, based on the complexity of the content of nuclear power production preparation plan, this paper briefly describes the optimization strategy of the preparatory work and the management work in the later stage, so as to promote the steady development of nuclear power industry. 展开更多
关键词 nuclear power production preparation PLAN
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Improved surface integrity in Inconel 718 using small diameter hammer peening tools
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作者 Aitor MADARIAGA Gorka ORTIZ-DE-ZARATE Pedro JoséARRAZOLA 《Chinese Journal of Aeronautics》 2025年第7期608-626,共19页
Machine Hammer Peening(MHP)is an emergent treatment that induces high compressive Residual Stresses(RS)which can enhance the in-service performance of components.This paper studies the use of small diameter MHP tools ... Machine Hammer Peening(MHP)is an emergent treatment that induces high compressive Residual Stresses(RS)which can enhance the in-service performance of components.This paper studies the use of small diameter MHP tools to improve the Surface Integrity(SI)of the nickel-based alloy Inconel 718 used in critical aero-engine components.Complementarily,the relaxation of RS is analyzed by in-situ annealing tests at in-service temperature combined with X-ray diffraction measurement.For this purpose,age hardened Inconel 718 discs were turned as reference condition,and then a pneumatic MHP tool was used under different conditions:two tool diameters(4 mm and 12 mm),feed rates(2.5 m/min and 5.0 m/min)and stepover distances(0.07 mm and 0.35 mm).Subsequently,surface topography characterization,RS measurements,nanoindentation tests,and microstructural observations were conducted.The in-situ annealing tests were done in the X-ray diffractometer at 550°C for exposure periods from 0 to 20 h.The results demonstrate that 4 mm diameter tools generate smooth surfaces and induce significant compressive RS within a0.5 mm thick layer.Residual stresses are relaxed,but they remain compressive even after a long thermal exposure.The microstructure of the surface layer(<10–15μm)was affected by the preceding turning operation,but importantly,MHP did not induce additional damage. 展开更多
关键词 In-situ tests Machine hammer peening Nickel-based alloy Residual stresses Surface integrity X-ray diffraction
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Comparative Toxicological Effects of Silica and Nanosilica against Trogoderma granarium under Variable Temperature Conditions
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作者 Doha A.El-Gendy Asmaa Z.El Sharkawy +2 位作者 Doaa S.Farghaly Salwa A.Rizk Rehab M.Sayed 《Journal of Environmental & Earth Sciences》 2025年第3期88-98,共11页
According the importance of the stored grains and other products,it is an essential to keep them from khapra beetle,Trogoderma granarium infestation.This study determined the mortality percentage of 5th instar larvae ... According the importance of the stored grains and other products,it is an essential to keep them from khapra beetle,Trogoderma granarium infestation.This study determined the mortality percentage of 5th instar larvae of T.granarium fed on wheat seeds(25 gm)treated with different weights of silica as well as silica nanoparticles(20,40,60 and 80 mg)at different temperature(9℃,25℃,and 35℃).Study showed that using silica nanoparticles in cold temperature(9℃)was the most efficient treatment with the lowest LC_(50)(lethal concentration required to kill 50%of the population)value and caused the highest toxicity index.In contrast,the least efficient treatment(25℃)with the highest LC_(50) value and showed lowest toxicity index was using silica in normal temperature,when using silica nanoparticles,the cold temperature was the best condition followed by hot temperature(35℃)and finally the normal temperature.On the other hand,using silica in hot temperature was most effective followed by silica with cold temperature and finally silica with normal temperature.The biochemical assays revealed that the change in the experimental temperature had a nonsignificant effect on the total protein content of the larvae.The total lipids and total carbohydrates exhibited a significant increase due to hot treating.5th instar larvae of T.granarium treated with LC50 of silica at high temperature led to a nonsignificant(p≤0.05)decrease in Acetylcholinesterase(AchE)activity compared to treatment at normal temperature.In contrast,Glutathione S-transferase(GST)and Peroxidase activities were significantly(p≤0.05)raised due to the treatment conducted at high temperature.Additionally,treating larvae with LC50 of silica nanoparticles at low temperature caused a significant increase in both GST and peroxidase activities,while the increase in AChE was nonsignificantly(p≤0.05)compared to treatment at normal temperature.Using silica at low temperature could be used as an alternative to chemical insecticides to control T.granarium larvae. 展开更多
关键词 Biochemical Studies Control Khapra Beetle NANOSILICA SILICA Temperature
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Characteristics of Wood Sponge from Sengon (Falcataria moluccana)Wood Manufacturing through a Multistage Delignification Process
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作者 Aisyah Zakiya Darajat Imam Wahyudi +2 位作者 Narto Adik Bahanawan Sarah Augustina 《Journal of Renewable Materials》 2025年第8期1661-1681,共21页
Adsorbents with three-dimensional porous structures have gained widespread attention due to their unique characteristics,including a large surface area,high porosity,and excellent absorption capacity.One of the produc... Adsorbents with three-dimensional porous structures have gained widespread attention due to their unique characteristics,including a large surface area,high porosity,and excellent absorption capacity.One of the products is the wood sponge.The key to successfully producing wood sponges lies in an optimal multistage delignification process,which is particularly influenced by wood species,solvent,time,and temperature.The aim of this research was to analyze the characteristics of wood sponge derived from sengon wood(Falcataria moluccana Miq.)after multistage delignification.The process involved delignification using NaOH and Na_(2)SO_(3) solutions at 100℃ for 8,9 and 10 h,followed by further delignification in H_(2)O_(2) solution at 100℃ for 1,2,3,and 4 h.The samples were then frozen at -20℃ for 24 h and freeze-dried at -53℃ for 48 h.The results showed that wood sponges treated at 100℃ exhibited lower density,larger pore diameters,brighter color,and superior absorption capacity compared to untreated wood and sponges treated at room temperature for 24 h.FTIR analysis confirmed a decrease in wavelength between 1032–1035 cm^(-1),indicating the degradation of hemicellulose and lignin.XRD analysis revealed that crystallinity increased as amorphous content decreased with prolonged delignification.The wood sponges demonstrated good porosity,with an absorption capacity ranging from 0.65 to 2.24 g/g.The optimal treatment suggested in this research was multistage delignification using NaOH and Na_(2)SO_(3) solution for 10 h,followed by a 1 h treatment with H_(2)O_(2) solution. 展开更多
关键词 Absorption capacity DELIGNIFICATION POROSITY sengon wood sponge
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Corrosion behavior and performance degradation of aluminum-copper cable joints with magnetic pulse crimping in salt spray environment
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作者 Yuan-heng YAO Shao-luo WANG +4 位作者 Hao JIANG Jun-jia CUI Guang-yao LI Kai-dong LUO Ling-hua XIA 《Transactions of Nonferrous Metals Society of China》 2025年第6期1937-1955,共19页
The corrosion resistance of aluminum(Al)cable-copper(Cu)terminal joints fabricated by magnetic pulse crimping(MPC)and hydraulic clamp crimping(HCC)was compared.Performance degradation was evaluated by mechanical and e... The corrosion resistance of aluminum(Al)cable-copper(Cu)terminal joints fabricated by magnetic pulse crimping(MPC)and hydraulic clamp crimping(HCC)was compared.Performance degradation was evaluated by mechanical and electrical properties.Additionally,corrosion behavior was analyzed by electrochemical testing.Microscopic characterization was performed by scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS).Results show that the tensile strength of the corroded joints is reduced.However,due to the advantages of high-speed forming and contact tightness unique to MPC,the contact resistance of the corroded joints still maintains excellent.Electrochemical tests demonstrate that the MPC joints have higher corrosion potentials and smaller corrosion currents,providing better corrosion resistance.The formation of a primary battery between Al and Cu at the lap joint leads to the formation of severer corrosion pits. 展开更多
关键词 magnetic pulse crimping aluminum−copper cable joint salt spray corrosion performance degradation corrosion mechanism
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Nonlinear Post-Buckling Stability of Graphene Origami-Enabled Auxetic Metamaterials Plates
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作者 Salwa A.Mohamed Mohamed A.Eltaher +1 位作者 Nazira Mohamed Rasha Abo-bakr 《Computer Modeling in Engineering & Sciences》 2025年第4期515-538,共24页
The nonlinear post-buckling response of functionally graded(FG)copper matrix plates enforced by graphene origami auxetic metamaterials(GOAMs)is investigated in the currentwork.The auxeticmaterial properties of the pla... The nonlinear post-buckling response of functionally graded(FG)copper matrix plates enforced by graphene origami auxetic metamaterials(GOAMs)is investigated in the currentwork.The auxeticmaterial properties of the plate are controlled by graphene content and the degree of origami folding,which are graded across the thickness of the plate.Thematerial properties of the GOAM plate are evaluated using genetic micro-mechanicalmodels.Governing nonlinear eigenvalue problems for the post-buckling response of the GOAM composite plate are derived using the virtual work principle and a four-variable nonlinear shear deformation theory.A novel differential quadrature method(DQM)algorithm is developed to solve the nonlinear eigenvalue problem.Detailed parametric studies are presented to explore the effects of graphene content,folding degree,and GO distribution patterns on the post-buckling responses of GOAM plates.Results show that high tunability in post-buckling characteristics can be achieved by using GOAM.FunctionallyGradedGraphene OrigamiAuxeticMetamaterials(FG-GOAM)plates can be used in aerospace structures to improve their structural performance and response. 展开更多
关键词 POSTBUCKLING nonlinear stability auxetic metamaterials higher order plate DQM numerical solution
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Research on Railway 5G-R Network Security Technology
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作者 ZHANG Song WANG Wei +3 位作者 TIAN Zhiji MA Jun SUN Bin SHEN Meiying(Translated) 《Chinese Railways》 2025年第1期29-36,共8页
The 5G-R network is on the verge of entering the construction stage.Given that the dedicated network for railways is closely linked to train operation safety,there are extremely high requirements for network security.... The 5G-R network is on the verge of entering the construction stage.Given that the dedicated network for railways is closely linked to train operation safety,there are extremely high requirements for network security.As a result,there is an urgent need to conduct research on 5G-R network security.To comprehensively enhance the end-to-end security protection of the 5G-R network,this study summarized the security requirements of the GSM-R network,analyzed the security risks and requirements faced by the 5G-R network,and proposed an overall 5G-R network security architecture.The security technical schemes were detailed from various aspects:5G-R infrastructure security,terminal access security,networking security,operation and maintenance security,data security,and network boundary security.Additionally,the study proposed leveraging the 5G-R security situation awareness system to achieve a comprehensive upgrade from basic security technologies to endogenous security capabilities within the 5G-R system. 展开更多
关键词 5G-R network security security risks endogenous security situational awareness
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Nanoparticles and Phytohormonal Synergy in Plants: Sustainable Agriculture Approach
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作者 Hafiza Muniba Din Muhammad Safina Naz +3 位作者 Zarina Bibi Mohamed A.A.Ahmed Alina-Stefania Stanciu Riaz Ahmad 《Phyton-International Journal of Experimental Botany》 2025年第9期2631-2648,共18页
The production of crops is badly affected by climate change globally.Mitigation of adverse effects of climate change is in need of time through different management practices such as developing tolerant genetic resour... The production of crops is badly affected by climate change globally.Mitigation of adverse effects of climate change is in need of time through different management practices such as developing tolerant genetic resources,hormonal applications to boost defense systems,nanoparticles,and balanced fertilization.The nano-hormonal syn-ergy had the potential to mitigate the adverse effects of climate change by modulation of morpho-physiological and biochemical activities.Plant growth,yield,and quality can be enhanced with the supplementation of nano-hormonal interactions.Therefore,the current study explores the synergy between nanoparticles and phytohormonal use.The nanoparticles,even in low concentrations,had an excellent capability to improve the endogenous hormones contributing to the regulation of plant responses under stress conditions.Nano-hormonal interaction improved the plant tolerance against climate change by activation of signaling molecules and the plant defense system.Nano-hormonal contact triggers several enzymic and non-enzymatic activities that can scavenge toxic substances generated within the plants.The reduction in electrolyte leakage,malondialdehyde(MDA),and hydrogen peroxide(H_(2)O_(2))was due to the supplementation of nano-hormonal exchange.The optimum production of reactive oxygen species(ROS)is necessary for normal plant growth and various developmental processes.However,the overproduction of ROS can be eliminated with nano-hormonal synergy.However,inappropriate applications can cause phytotoxicity such as germination inhibition,root malformation,and chlorosis.The optimum doses can vary depending on the kind of crop and stress conditions.The nano-hormonal interface is beneficial for crop growth,yield,and quality.Moreover,these are also effective in repairing plants damaged from adverse climatic conditions.Hence,these are effective for sustainable agriculture production. 展开更多
关键词 ANTIOXIDANTS growth characters METABOLITES TRANSCRIPTOMICS YIELD
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Sero-Prevalence of Peste des Petits Ruminants Virus Antibodies in Sudanese Sheep and Goats before and after Vaccination
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作者 Omer Algezoli Selma Kamal +8 位作者 Yazeed Raouf Alamin Mozdalifa Hiba Ali Mohamed Aljameel Salih Sir Elkhatim Sulieman Ahmed Ibtesam Fadul Elsied Tageldin Nour Mohamed Abdalla 《Journal of Biosciences and Medicines》 2025年第1期21-40,共20页
Peste des petits ruminants virus (PPRV) antibodies were studied in Sudanese sheep and goats (n = 855) before and after vaccination with a locally produced Nigeria 75/1 vaccine using a commercial competitive ELISA (cEL... Peste des petits ruminants virus (PPRV) antibodies were studied in Sudanese sheep and goats (n = 855) before and after vaccination with a locally produced Nigeria 75/1 vaccine using a commercial competitive ELISA (cELISA) kit. Animals were kept healthy under field conditions, in four states: Blue Nile (n = 250), North Kordofan (n = 189), South Darfur (n = 225) and the Northern State (n = 191). Before vaccination, the overall sero-prevalence of PPRV antibodies was 54.6% (53.2% - 56%, 95% CI);high (64.8% - 76.4%, 95% CI) in Blue Nile State, medium (50.5% - 61.9%, 95% CI) in North Kordofan State and South Darfur State and low (28.6% - 35.2% 95%, CI) in Northern State. In high-risk areas (high sero-prevalence), Blue Nile (70.4%) and North Kordofan (57.7%), middle age groups (7 - 12 and 13 - 18 months) were identified as high-risk age. Middle age groups showed lower sero-prevalence than preceding (3 - 6 months) and subsequent (>18 months) age groups while the risk of exposure increased with age. Current and previous findings suggested a transmission pathway of PPRV involving the South Eastern border (Blue Nile) and neighbouring Central Sudan to North Kordofan. One month after vaccination 88.4% (343/388) of sero-negative animals were sero-converted suggesting the efficacy of the locally produced Nigeria 75/1 vaccine. Even if only individuals in the high-risk age group (7 - 18 months) were vaccinated, the overall population immunity (OPI) in high-risk areas (the Blue Nile and North Kordofan) would have surpassed the threshold of 70%, which is indicated for blocking PPRV transmission. However, lower vaccination coverage is expected in wider vaccination programmes. These findings primarily justified the targeting of PPR control in Sudan through the vaccination of high-risk age groups in high-risk areas. 展开更多
关键词 Peste des Petits Ruminants (PPR) Vaccination Efficacy SEROPREVALENCE Herd Immunity High-Risk Area
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