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Dietary xylo‑oligosaccharides and arabinoxylans improved growth efficiency by reducing gut epithelial cell turnover in broiler chickens 被引量:1
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作者 Carla Castro Shahram Niknafs +3 位作者 Gemma Gonzalez‑Ortiz Xinle Tan Michael R.Bedford Eugeni Roura 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1325-1335,共11页
Background One of the main roles of the intestinal mucosa is to protect against environmental hazards.Supple-mentation of xylo-oligosaccharides(XOS)is known to selectively stimulate the growth of beneficial intestinal... Background One of the main roles of the intestinal mucosa is to protect against environmental hazards.Supple-mentation of xylo-oligosaccharides(XOS)is known to selectively stimulate the growth of beneficial intestinal bacteria and improve gut health and function in chickens.XOS may have an impact on the integrity of the intestinal epithelia where cell turnover is critical to maintain the compatibility between the digestive and barrier functions.The aim of the study was to evaluate the effect of XOS and an arabinoxylan-rich fraction(AXRF)supplementation on gut func-tion and epithelial integrity in broiler chickens.Methods A total of 128 broiler chickens(Ross 308)were assigned into one of two different dietary treatments for a period of 42 d:1)control diet consisting of a corn/soybean meal-based diet;or 2)a control diet supplemented with 0.5%XOS and 1%AXRF.Each treatment was randomly distributed across 8 pens(n=8)with 8 chickens each.Feed intake and body weight were recorded weekly.On d 42,one male chicken per pen was selected based on aver-age weight and euthanized,jejunum samples were collected for proteomics analysis.Results Dietary XOS/AXRF supplementation improved feed efficiency(P<0.05)from d 1 to 42 compared to the con-trol group.Proteomic analysis was used to understand the mechanism of improved efficiency uncovering 346 dif-ferentially abundant proteins(DAP)(Padj<0.00001)in supplemented chickens compared to the non-supplemented group.In the jejunum,the DAP translated into decreased ATP production indicating lower energy expenditure by the tissue(e.g.,inhibition of glycolysis and tricarboxylic acid cycle pathways).In addition,DAP were associated with decreased epithelial cell differentiation,and migration by reducing the actin polymerization pathway.Put-ting the two main pathways together,XOS/AXRF supplementation may decrease around 19%the energy required for the maintenance of the gastrointestinal tract.Conclusions Dietary XOS/AXRF supplementation improved growth efficiency by reducing epithelial cell migration and differentiation(hence,turnover),actin polymerization,and consequently energy requirement for maintenance of the jejunum of broiler chickens. 展开更多
关键词 ACTIN ARABINOXYLANS BROILER Cell turnover Energy metabolism JEJUNUM Xylo-oligosaccharides
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透明ABS树脂的技术与市场展望
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作者 陈明 李微 +3 位作者 李国锋 兰苗宇 王宇超 陆书来 《弹性体》 CAS 2024年第3期93-96,共4页
介绍了透明ABS树脂的制备工艺,透明ABS树脂的生产工艺及其制备过程中的关键机理,重点强调了橡胶相与树脂相折光指数的匹配方法,以及增韧粒子结构对透明ABS树脂性能的影响,并对透明ABS树脂的技术现状及市场发展趋势进行了分析和预测。
关键词 透明ABS树脂 微观结构 技术现状 发展趋势
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凝聚剂组成对G-ABS高胶粉及ABS外观特性的影响
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作者 刘姜 李柏静 +3 位作者 于万权 姜山 张辉 陆书来 《合成树脂及塑料》 CAS 北大核心 2024年第4期19-23,共5页
在使用凝聚剂从聚丁二烯与丙烯腈和苯乙烯的接枝共聚物(G-ABS)胶乳中回收G-ABS高胶粉的过程中,凝聚剂组成不但会改变高胶粉的粒径,还会对丙烯腈-丁二烯-苯乙烯三元共聚物(ABS)粒料的白度和色度稳定性造成影响。以冰乙酸/硫酸镁、硫酸/... 在使用凝聚剂从聚丁二烯与丙烯腈和苯乙烯的接枝共聚物(G-ABS)胶乳中回收G-ABS高胶粉的过程中,凝聚剂组成不但会改变高胶粉的粒径,还会对丙烯腈-丁二烯-苯乙烯三元共聚物(ABS)粒料的白度和色度稳定性造成影响。以冰乙酸/硫酸镁、硫酸/硫酸镁为凝聚剂,通过调整阳离子的配比,对比2组凝聚剂对G-ABS高胶粉和ABS外观特性的影响。结果表明:在确保凝聚浆液为酸性时,减少凝聚剂阳离子中H+占比,对粉料筛分粒径分布、氧化诱导时间没有明显影响,但ABS白度、热氧老化色度稳定性和粒料储存色度稳定性均有提升;与使用硫酸相比,使用冰乙酸能够显著提升ABS白度和热氧老化色度稳定性。 展开更多
关键词 高胶粉 凝聚剂组成 白度 色度稳定性
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ABS无磷、无糖接枝聚合反应过程优化研究
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作者 姜山 刘姜 +3 位作者 李国锋 陆书来 张辉 张馨元 《塑料工业》 CAS CSCD 北大核心 2024年第5期56-62,139,共8页
丙烯腈-丁二烯-苯乙烯三元共聚物(ABS)接枝聚合使用由甲醛次硫酸钠(SFS)、乙二胺四乙酸四钠(EDTA-4Na)和硫酸亚铁(FES)组成的还原剂时,氧化剂、还原剂以及接枝单体的不同加入方式对反应速率和接枝过程都有较大影响。采用“预补/全程连... 丙烯腈-丁二烯-苯乙烯三元共聚物(ABS)接枝聚合使用由甲醛次硫酸钠(SFS)、乙二胺四乙酸四钠(EDTA-4Na)和硫酸亚铁(FES)组成的还原剂时,氧化剂、还原剂以及接枝单体的不同加入方式对反应速率和接枝过程都有较大影响。采用“预补/全程连续”方式加入还原剂,连续滴加方式加入氧化剂和接枝单体,能够实现对整个反应阶段引发剂分解产生自由基的速率的精准调控,改善接枝效果,提升粉料的增韧效率。 展开更多
关键词 丙烯腈-丁二烯-苯乙烯三元共聚物 接枝聚合 氧化-还原引发体系 无磷 无糖 反应过程优化
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ABS树脂热稳定性能评价方法研究Ⅱ多次挤出法评价ABS树脂性能
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作者 王宇超 兰苗宇 +4 位作者 李微 陈明 宋利忠 陈兴郁 陆书来 《化工科技》 2024年第6期42-47,共6页
测试添加不同抗氧剂的ABS树脂在反复挤出过程后的性能变化。实验结果表明,经过5次重复挤出作用后,添加抗氧剂302的ABS试样初始分解温度T10%由381.3℃提高到411.8℃,黄色指数从35.23降低到32.16,表现出对ABS优异的热氧稳定性和色度保持性... 测试添加不同抗氧剂的ABS树脂在反复挤出过程后的性能变化。实验结果表明,经过5次重复挤出作用后,添加抗氧剂302的ABS试样初始分解温度T10%由381.3℃提高到411.8℃,黄色指数从35.23降低到32.16,表现出对ABS优异的热氧稳定性和色度保持性;添加抗氧剂618的ABS试样将氧化诱导温度由192.9℃提高到了217.4℃;添加抗氧剂3114的ABS试样的熔融指数由21.76 g/(10 min)提高到21.95 g/(10 min)。 展开更多
关键词 多次挤出法 ABS树脂 抗氧剂 热氧稳定性
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From VIB‑to VB‑Group Transition Metal Disulfides:Structure Engineering Modulation for Superior Electromagnetic Wave Absorption 被引量:2
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作者 Junye Cheng Yongheng Jin +10 位作者 Jinghan Zhao Qi Jing Bailong Gu Jialiang Wei Shenghui Yi Mingming Li Wanli Nie Qinghua Qin Deqing Zhang Guangping Zheng Renchao Che 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期218-257,共40页
The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various field... The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various fields,such as catalysis,energy storage,sensing,etc.In recent years,a lot of research work on TMDs based functional materials in the fields of electromagnetic wave absorption(EMA)has been carried out.Therefore,it is of great significance to elaborate the influence of TMDs on EMA in time to speed up the application.In this review,recent advances in the development of electromagnetic wave(EMW)absorbers based on TMDs,ranging from the VIB group to the VB group are summarized.Their compositions,microstructures,electronic properties,and synthesis methods are presented in detail.Particularly,the modulation of structure engineering from the aspects of heterostructures,defects,morphologies and phases are systematically summarized,focusing on optimizing impedance matching and increasing dielectric and magnetic losses in the EMA materials with tunable EMW absorption performance.Milestones as well as the challenges are also identified to guide the design of new TMDs based dielectric EMA materials with high performance. 展开更多
关键词 Transition metal disulfides Electromagnetic wave absorption Impedance matching Structure engineering modulation
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Evaluation of soil erosion vulnerability in Hubei Province of China using RUSLE model and combination weighting method
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作者 YANG Yanpan TIAN Pei +3 位作者 JIA Tinghui WANG Fei YANG Yang HUANG Jianwu 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3318-3336,共19页
Soil erosion has been recognized as a critical environmental issue worldwide.While previous studies have primarily focused on watershed-scale soil erosion vulnerability from a natural factor perspective,there is a not... Soil erosion has been recognized as a critical environmental issue worldwide.While previous studies have primarily focused on watershed-scale soil erosion vulnerability from a natural factor perspective,there is a notable gap in understanding the intricate interplay between natural and socio-economic factors,especially in the context of spatial heterogeneity and nonlinear impacts of human-land interactions.To address this,our study evaluates the soil erosion vulnerability at a provincial scale,taking Hubei Province as a case study to explore the combined effects of natural and socio-economic factors.We developed an evaluation index system based on 15 indicators of soil erosion vulnerability:exposure,sensitivity,and adaptability.In addition,the combination weighting method was applied to determine index weights,and the spatial interaction was analyzed using spatial autocorrelation,geographical temporally weighted regression and geographical detector.The results showed an overall decreasing soil erosion intensity in Hubei Province during 2000 and 2020.The soil erosion vulnerability increased before 2000 and then.The areas with high soil erosion vulnerability were mainly confined in the central and southern regions of Hubei Province(Xiantao,Tianmen,Qianjiang and Ezhou)with obvious spatial aggregation that intensified over time.Natural factors(habitat quality index)had negative impacts on soil erosion vulnerability,whereas socio-economic factors(population density)showed substantial spatial variability in their influences.There was a positive correlation between soil erosion vulnerability and erosion intensity,with the correlation coefficients ranging from-0.41 and 0.93.The increase of slope was found to enhance the positive correlation between soil erosion vulnerability and intensity. 展开更多
关键词 Soil erosion vulnerability RUSLE model Combination weighting method Driving factors Spatial heterogeneity
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Towards trustworthy multi-modal motion prediction:Holistic evaluation and interpretability of outputs
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作者 Sandra Carrasco Limeros Sylwia Majchrowska +3 位作者 Joakim Johnander Christoffer Petersson MiguelÁngel Sotelo David Fernández Llorca 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第3期557-572,共16页
Predicting the motion of other road agents enables autonomous vehicles to perform safe and efficient path planning.This task is very complex,as the behaviour of road agents depends on many factors and the number of po... Predicting the motion of other road agents enables autonomous vehicles to perform safe and efficient path planning.This task is very complex,as the behaviour of road agents depends on many factors and the number of possible future trajectories can be consid-erable(multi-modal).Most prior approaches proposed to address multi-modal motion prediction are based on complex machine learning systems that have limited interpret-ability.Moreover,the metrics used in current benchmarks do not evaluate all aspects of the problem,such as the diversity and admissibility of the output.The authors aim to advance towards the design of trustworthy motion prediction systems,based on some of the re-quirements for the design of Trustworthy Artificial Intelligence.The focus is on evaluation criteria,robustness,and interpretability of outputs.First,the evaluation metrics are comprehensively analysed,the main gaps of current benchmarks are identified,and a new holistic evaluation framework is proposed.Then,a method for the assessment of spatial and temporal robustness is introduced by simulating noise in the perception system.To enhance the interpretability of the outputs and generate more balanced results in the proposed evaluation framework,an intent prediction layer that can be attached to multi-modal motion prediction models is proposed.The effectiveness of this approach is assessed through a survey that explores different elements in the visualisation of the multi-modal trajectories and intentions.The proposed approach and findings make a significant contribution to the development of trustworthy motion prediction systems for autono-mous vehicles,advancing the field towards greater safety and reliability. 展开更多
关键词 autonomous vehicles EVALUATION INTERPRETABILITY multi-modal motion prediction ROBUSTNESS trustworthy AI
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False Positive HIV “Combo” Screening Test in a Hemodialysis Patient in Saudi Arabia: A Case Report and Review of the Literature
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作者 Ngozi Virginia Aikpokpo Ahmed Yayha Omaysh 《Case Reports in Clinical Medicine》 2024年第9期366-374,共9页
Introduction: HIV screening tests are routinely conducted on dialysis patients as the constant exposure of their blood during the dialysis process makes them a reasonable risk for blood-borne infections. However, in l... Introduction: HIV screening tests are routinely conducted on dialysis patients as the constant exposure of their blood during the dialysis process makes them a reasonable risk for blood-borne infections. However, in low prevalence settings, where HIV rates are <0.1% of the population, false positive results are more likely. This results in apprehension in the dialysis unit as breaches in infectious disease protocols could be presumed. This is illustrated in the case report below. Case Summary: A 62-year-old male Saudi end-stage kidney disease patient secondary to DM nephropathy began dialysis a year before presentation in a hemodialysis center in Saudi Arabia. Routine screening tests done at the start of dialysis revealed negative Hepatitis C, HIV 1 and 2 screening but a positive Hepatitis B surface antigen screen. The patient went for holiday dialysis at another facility and had a routine fourth-generation HIV test done which was positive. A confirmatory HIV PCR test was negative. Conclusion: This case highlights the need for caution in interpreting highly sensitive and specific HIV screening tests in a low-prevalence setting. Routine screening beyond the national recommendation may not be necessary in low-prevalence areas. 展开更多
关键词 Saudi Arabia False Positive HIV Test HEMODIALYSIS
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Ultrathin Zincophilic Interphase Regulated Electric Double Layer Enabling Highly Stable Aqueous Zinc‑Ion Batteries 被引量:2
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作者 Yimei Chen Zhiping Deng +5 位作者 Yongxiang Sun Yue Li Hao Zhang Ge Li Hongbo Zeng Xiaolei Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期285-299,共15页
The practical application of aqueous zinc-ion batteries for large-grid scale systems is still hindered by uncontrolled zinc dendrite and side reactions.Regulating the elec-trical double layer via the electrode/electro... The practical application of aqueous zinc-ion batteries for large-grid scale systems is still hindered by uncontrolled zinc dendrite and side reactions.Regulating the elec-trical double layer via the electrode/electrolyte interface layer is an effective strategy to improve the stability of Zn anodes.Herein,we report an ultrathin zincophilic ZnS layer as a model regu-lator.At a given cycling current,the cell with Zn@ZnS electrode displays a lower potential drop over the Helmholtz layer(stern layer)and a suppressed diffuse layer,indicating the regulated charge distribution and decreased electric double layer repulsion force.Boosted zinc adsorption sites are also expected as proved by the enhanced electric double-layer capacitance.Consequently,the symmetric cell with the ZnS protection layer can stably cycle for around 3,000 h at 1 mA cm^(-2) with a lower overpotential of 25 mV.When coupled with an I2/AC cathode,the cell demonstrates a high rate performance of 160 mAh g^(-1) at 0.1 A g^(-1) and long cycling stability of over 10,000 cycles at 10 A g^(-1).The Zn||MnO_(2) also sustains both high capacity and long cycling stability of 130 mAh g^(-1) after 1,200 cycles at 0.5 A g^(-1). 展开更多
关键词 Zinc anode Electric double-layer regulation Multifunction SEI layer Inhibited side reactions and dendrite Rapid kinetics
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Actively tunable sandwich acoustic metamaterials with magnetorheological elastomers
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作者 Jinhui LIU Yu XUE +2 位作者 Zhihong GAO A.O.KRUSHYNSKA Jinqiang LI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第11期1875-1894,共20页
Sandwich structures are widespread in engineering applications because of their advantageous mechanical properties.Recently,their acoustic performance has also been improved to enable attenuation of low-frequency vibr... Sandwich structures are widespread in engineering applications because of their advantageous mechanical properties.Recently,their acoustic performance has also been improved to enable attenuation of low-frequency vibrations induced by noisy environments.Here,we propose a new design of sandwich plates(SPs)featuring a metamaterial core with an actively tunable low-frequency bandgap.The core contains magnetorheological elastomer(MRE)resonators which are arranged periodically and enable controlling wave attenuation by an external magnetic field.We analytically estimate the sound transmission loss(STL)of the plate using the space harmonic expansion method.The low frequency sound insulation performance is also analyzed by the equivalent dynamic density method,and the accuracy of the obtained results is verified by finite-element simulations.Our results demonstrate that the STL of the proposed plate is enhanced compared with a typical SP analog,and the induced bandgap can be effectively tuned to desired frequencies.This study further advances the field of actively controlled acoustic metamaterials,and paves the way to their practical applications. 展开更多
关键词 sandwich plate(SP) magnetorheological elastomer(MRE) sound transmission loss(STL) vibration control acoustic metamaterial
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ABS树脂冲击强度测试的影响因素 被引量:3
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作者 宋振彪 王毅 +2 位作者 许忠林 胡慧林 陆书来 《弹性体》 CAS 北大核心 2021年第1期48-52,共5页
对比了4个牌号ABS树脂ASTM标准和国标悬臂梁冲击强度,剖析了ABS树脂橡胶相组成对测试结果的影响,并运用moldflow软件模拟冲击样件注塑成型过程,分析引起冲击强度测试结果差异的原因。结果表明,通过降低冲击测试样条注塑成型注塑速度减... 对比了4个牌号ABS树脂ASTM标准和国标悬臂梁冲击强度,剖析了ABS树脂橡胶相组成对测试结果的影响,并运用moldflow软件模拟冲击样件注塑成型过程,分析引起冲击强度测试结果差异的原因。结果表明,通过降低冲击测试样条注塑成型注塑速度减小样件表面剪切应力的方法,能够提高冲击强度测试结果,较高的橡胶含量可以减弱注塑速度的影响程度,不同的试验标准和试验条件对ABS树脂冲击强度试验结果的影响不同,因此原料评选过程中需要运用不同方法比较材料的冲击性能。 展开更多
关键词 ABS树脂 冲击强度 注塑工艺 测试技术
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橡胶含量对ABS成品性能的影响 被引量:4
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作者 兰正勇 王娴慧 +2 位作者 宋利忠 刘清铃 姜海容 《合成树脂及塑料》 CAS 2003年第5期40-42,共3页
以橡胶含量为40%和60%的丙烯腈-丁二烯-苯乙烯共聚物(ABS)粉料分别与苯乙烯/丙烯腈共聚物掺混造粒,制备一系列不同橡胶含量的ABS成品,分析了不同橡胶含量ABS成品性能,比较了高橡胶含量和低橡胶含量的ABS粉料对成品性能的影响。研究结果... 以橡胶含量为40%和60%的丙烯腈-丁二烯-苯乙烯共聚物(ABS)粉料分别与苯乙烯/丙烯腈共聚物掺混造粒,制备一系列不同橡胶含量的ABS成品,分析了不同橡胶含量ABS成品性能,比较了高橡胶含量和低橡胶含量的ABS粉料对成品性能的影响。研究结果发现,在橡胶含量相同的情况下,使用高橡胶含量的ABS粉料,成品的力学性能较为优异。 展开更多
关键词 橡胶含量 ABS 产品性能 丙烯腈-丁二烯-苯乙烯共聚物 粉料
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Facilitated Prediction of Micropollutant Degradation via UV-AOPs in Various Waters by Combining Model Simulation and Portable Measurement
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作者 Yanyan Huang Mengkai Li +3 位作者 Zhe Sun Wentao Li James R.Bolton Zhimin Qiang 《Engineering》 SCIE EI CAS CSCD 2024年第6期87-95,共9页
The degradation of micropollutants in water via ultraviolet(UV)-based advanced oxidation processes(AOPs)is strongly dependent on the water matrix.Various reactive radicals(RRs)formed in UV-AOPs have different reaction... The degradation of micropollutants in water via ultraviolet(UV)-based advanced oxidation processes(AOPs)is strongly dependent on the water matrix.Various reactive radicals(RRs)formed in UV-AOPs have different reaction selectivities toward water matrices and degradation efficiencies for target micropollutants.Hence,process selection and optimization are crucial.This study developed a facilitated prediction method for the photon fluence-based rate constant for micropollutant degradation(K′_(p,MP))in various UV-AOPs by combining model simulation with portable measurement.Portable methods for measuring the scavenging capacities of the principal RRs(RRSCs)involved in UV-AOPs(i.e.,HO^(·),SO_(4)^(·-),and Cl^(·))using a mini-fluidic photoreaction system were proposed.The simulation models consisted of photochemical,quantitative structure–activity relationship,and radical concentration steady-state approximation models.The RRSCs were determined in eight test waters,and a higher RRSC was found to be associated with a more complex water matrix.Then,by taking sulfamethazine,caffeine,and carbamazepine as model micropollutants,the k′_(p,MP) values in various UV-AOPs were predicted and further verified experimentally.A lower k′_(p,MP) was found to be associated with a higher RRSC for a stronger RR competition;for example,k′_(p,MP) values of 130.9 and 332.5 m^(2) einstein^(–1),respectively,were obtained for carbamazepine degradation by UV/H_(2)O_(2) in the raw water(RRSC=9.47×10^(4) s^(-1))and sand-filtered effluent(RRSC=2.87×10^(4) s^(-1))of a drinking water treatment plant.The developed method facilitates process selection and optimization for UV-AOPs,which is essential for increasing the efficiency and cost-effectiveness of water treatment. 展开更多
关键词 UV-AOPs Micropollutant degradation Reactive radicals Water matrix Model simulation
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2019年ABS树脂生产及市场分析 被引量:9
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作者 黄金霞 丁晓艳 +2 位作者 谢妤 陆书来 崔秀梅 《化学工业》 CAS 2020年第3期41-48,55,共9页
综述了2019年国内外ABS树脂生产情况;同时,对国内外ABS树脂市场及价格也进行了分析和预测;提出发展建议。
关键词 ABS树脂 生产 市场 价格 分析预测 建议
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Preparation and performance evaluation of the slickwater using novel polymeric drag reducing agent with high temperature and shear resistance ability
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作者 Ming-Wei Zhao Zhen-Feng Ma +5 位作者 Cai-Li Dai WeiWu Yong-Quan Sun Xu-Guang Song Yun-Long Cheng Xiang-Yu Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1113-1121,共9页
Slickwater fracturing fluids are widely used in the development of unconventional oil and gas resources due to the advantages of low cost,low formation damage and high drag reduction performance.However,their performa... Slickwater fracturing fluids are widely used in the development of unconventional oil and gas resources due to the advantages of low cost,low formation damage and high drag reduction performance.However,their performance is severely affected at high temperatures.Drag reducing agent is the key to determine the drag reducing performance of slickwater.In this work,in order to further improve the temperature resistance of slickwater,a temperature-resistant polymeric drag reducing agent(PDRA)was synthesized and used as the basis for preparing the temperature-resistant slickwater.The slickwater system was prepared with the compositions of 0.2 wt%PDRA,0.05 wt%drainage aid nonylphenol polyoxyethylene ether phosphate(NPEP)and 0.5 wt%anti-expansion agent polyepichlorohydrindimethylamine(PDM).The drag reduction ability,rheology properties,temperature and shear resistance ability,and core damage property of slickwater were systematically studied and evaluated.In contrast to on-site drag reducing agent(DRA)and HPAM,the temperature-resistant slickwater demonstrates enhanced drag reduction efficacy at 90℃,exhibiting superior temperature and shear resistance ability.Notably,the drag reduction retention rate for the slickwater achieved an impressive 90.52%after a 30-min shearing period.Additionally,the core damage is only 5.53%.We expect that this study can broaden the application of slickwater in high-temperature reservoirs and provide a theoretical basis for field applications. 展开更多
关键词 Unconventional resources Polymeric drag reducing agent Slickwater High drag reduction rate Temperature resistance
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Mechanics analysis of vehicle bumping at approach slabs with superelevation 被引量:4
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作者 姚辉 李亮 +1 位作者 谢桦 冯宇 《Journal of Southeast University(English Edition)》 EI CAS 2012年第2期221-228,共8页
In order to analyze the pavement stress caused by vehicle bumping at an approach slab, a simplified four-wheeled bi- axle vehicle-moving model is proposed. The effect of damping and vibration reduction in the process ... In order to analyze the pavement stress caused by vehicle bumping at an approach slab, a simplified four-wheeled bi- axle vehicle-moving model is proposed. The effect of damping and vibration reduction in the process of vehicle-moving is not considered. Based on the position change of vehicle wheels at the approach slab, the vehicle dynamic vibration equations are summarized. Meanwhile, the undetermined coefficients of the vibration equations are obtained using the boundary and initial conditions of the vehicle. The analytical motion solutions of rear and front wheels at different stages are concluded. Consequently, a four-wheeled vehicle model is developed and vibration equations are provided, which can be used to analyze the impact of complicated stress on pavement. The results show that the excessive stress and stress concentration will occur at the approach slab, and it needs to be strengthened. 展开更多
关键词 road engineering mechanics analysis approach slab vehicle model motion equation
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2018年国内外ABS树脂生产技术与市场 被引量:6
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作者 黄金霞 朱海林 +1 位作者 陈兴郁 陆书来 《化学工业》 CAS 2019年第4期33-41,共9页
分析了2018年国内外ABS树脂生产、市场供需情况。对ABS树脂未来市场应用的方向进行了预测,介绍了ABS树脂科研开发与技术进展,指出了ABS树脂未来的发展趋势和建议。
关键词 ABS树脂 生产 市场应用 科研开发 发展建议
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2017年ABS树脂生产与市场分析 被引量:6
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作者 黄金霞 宋仁刚 +1 位作者 朱海林 陆书来 《化学工业》 CAS 2018年第4期52-57,共6页
综述了2017年国内外ABS树脂生产商的生产能力和实际产量、国内外ABS树脂市场需求和价格,对国内外ABS树脂技术现状及其市场发展趋势进行了分析和预测。
关键词 ABS树脂 生产 市场 分析 建议
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Postbiotics from Saccharomyces cerevisiae fermentation stabilize microbiota in rumen liquid digesta during grain-based subacute ruminal acidosis(SARA) in lactating dairy cows
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作者 Junfei Guo Zhengxiao Zhang +3 位作者 Le Luo Guan Ilkyu Yoon Jan C.Plaizier Ehsan Khafipour 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期2059-2080,共22页
Background Subacute ruminal acidosis(SARA)is a common metabolic disorder of high yielding dairy cows,and it is associated with dysbiosis of the rumen and gut microbiome and host inflammation.This study evaluated the i... Background Subacute ruminal acidosis(SARA)is a common metabolic disorder of high yielding dairy cows,and it is associated with dysbiosis of the rumen and gut microbiome and host inflammation.This study evaluated the impact of two postbiotics from Saccharomyces cerevisiae fermentation products(SCFP)on rumen liquid associated microbiota of lactating dairy cows subjected to repeated grain-based SARA challenges.A total of 32 rumen cannulated cows were randomly assigned to 4 treatments from 4 weeks before until 12 weeks after parturition.Treatment groups included a Control diet or diets supplemented with postbiotics(SCFPa,14 g/d Original XPC;SCFPb-1X,19 g/d Nutri Tek;SCFPb-2X,38 g/d Nutri Tek,Diamond V,Cedar Rapids,IA,USA).Grain-based SARA challenges were conducted during week 5(SARA1)and week 8(SARA2)after parturition by replacing 20%DM of the base total mixed ration(TMR)with pellets containing 50%ground barley and 50%ground wheat.Total DNA from rumen liquid samples was subjected to V3–V416S r RNA gene amplicon sequencing.Characteristics of rumen microbiota were compared among treatments and SARA stages.Results Both SARA challenges reduced the diversity and richness of rumen liquid microbiota,altered the overall composition(β-diversity),and its predicted functionality including carbohydrates and amino acids metabolic pathways.The SARA challenges also reduced the number of significant associations among different taxa,number of hub taxa and their composition in the microbial co-occurrence networks.Supplementation with SCFP postbiotics,in particular SCFPb-2X,enhanced the robustness of the rumen microbiota.The SCFP supplemented cows had less fluctuation in relative abundances of community members when exposed to SARA challenges.The SCFP supplementation promoted the populations of lactate utilizing and fibrolytic bacteria,including members of Ruminococcaceae and Lachnospiraceae,and also increased the numbers of hub taxa during non-SARA and SARA stages.Supplementation with SCFPb-2X prevented the fluctuations in the abundances of hub taxa that were positively correlated with the acetate concentration,andα-andβ-diversity metrics in rumen liquid digesta.Conclusions Induction of SARA challenges reduced microbiota richness and diversity and caused fluctuations in major bacterial phyla in rumen liquid microbiota in lactating dairy cows.Supplementation of SCFP postbiotics could attenuate adverse effects of SARA on rumen liquid microbiota. 展开更多
关键词 Postbiotics Rumen microbiota Saccharomyces cerevisiae fermentation products SARA
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