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Effects of Biogas Slurry Application Years on Remediation of Pennisetum×sinese on Soil Physical and Chemical Properties and Microorganisms of Rare Earth Tailings
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作者 Shiyi FU Zhimei WANG +3 位作者 Wei LOU Zhiyong WU Sha LUO Guorong NI 《Agricultural Biotechnology》 2024年第6期22-27,33,共7页
[Objectives]This study was conducted to analyze the effects of continuous application of biogas slurry for many years on soil ecosystem restoration of rare earth tailings by planting Pennisetum×sinese,in order to... [Objectives]This study was conducted to analyze the effects of continuous application of biogas slurry for many years on soil ecosystem restoration of rare earth tailings by planting Pennisetum×sinese,in order to provide basis for scientific application of biogas slurry.[Methods]The fields with different years of continuous application of biogas slurry in Dingnan Rare Earth Tailings Ecological Restoration Demonstration Park were selected as the research object,and the differences in soil physical and chemical properties and microbial community structure after application of biogas slurry for different years(0,3 and 5 years)were studied.[Results]The bulk density of soil with continuous application of biogas slurry showed a downward trend,while the maximum water holding capacity,capillary water holding capacity,porosity,aeration,pH,organic matter,nitrogen,phosphorus and potassium,alkali-hydrolyzable nitrogen and available phosphorus showed an upward trend.Moreover,the effects achieved by application for 5 years were better than those by application for 3 years.Continuous application of biogas slurry could significantly improve the activity of soil urease,acid phosphatase,sucrase and cellulase,and it effects increased with the application year increasing.Continuous application of biogas slurry could significantly improve the abundance of dominant bacteria in soil,and with the increase of application years,the abundances of dominant bacteria also increased.[Conclusions]Continuous application of biogas slurry effectively improved soil physical and chemical properties and soil fertility in rare earth tailings areas where Pennisetum×sinese was planted to restore rare earth tailings.This study provides a theoretical support for establishing key ecological restoration technoiques. 展开更多
关键词 Biogas slurry application period Rare earth tailings Soil physical and chemical properties Soil microorganism
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3D rock physics template-based probabilistic estimation of tight sandstone reservoir properties
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作者 Hao-Jie Pan Chao Wei +4 位作者 Xin-Fei Yan Xiao-Ming Li Zhi-Fang Yang Zhi-Xian Gui Shu-Xian Liu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第5期3090-3101,共12页
Quantitative prediction of reservoir properties(e.g., gas saturation, porosity, and shale content) of tight reservoirs is of great significance for resource evaluation and well placements. However, the complex pore st... Quantitative prediction of reservoir properties(e.g., gas saturation, porosity, and shale content) of tight reservoirs is of great significance for resource evaluation and well placements. However, the complex pore structures, poor pore connectivity, and uneven fluid distribution of tight sandstone reservoirs make the correlation between reservoir parameters and elastic properties more complicated and thus pose a major challenge in seismic reservoir characterization. We have developed a partially connected double porosity model to calculate elastic properties by considering the pore structure and connectivity, and to analyze these factors' influences on the elastic behaviors of tight sandstone reservoirs. The modeling results suggest that the bulk modulus is likely to be affected by the pore connectivity coefficient, while the shear modulus is sensitive to the volumetric fraction of stiff pores. By comparing the model predictions with the acoustic measurements of the dry and saturated quartz sandstone samples, the volumetric fraction of stiff pores and the pore connectivity coefficient can be determined. Based on the calibrated model, we have constructed a 3D rock physics template that accounts for the reservoir properties' impacts on the P-wave impedance, S-wave impedance, and density. The template combined with Bayesian inverse theory is used to quantify gas saturation, porosity, clay content, and their corresponding uncertainties from elastic parameters. The application of well-log and seismic data demonstrates that our 3D rock physics template-based probabilistic inversion approach performs well in predicting the spatial distribution of high-quality tight sandstone reservoirs in southwestern China. 展开更多
关键词 Tight sandstones Pore structure 3D rock physics template Seismic inversion Reservoir property estimation
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Effects of Different Nitrogen Applications on Soil Physical, Chemical Properties and Yield in Maize (<i>Zea mays</i>L.) 被引量:3
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作者 Heng Zhong Qiao Wang +8 位作者 Xinhua Zhao Qi Du Yue Zhao Xiaoguang Wang Chunji Jiang Shuli Zhao Minjian Cao Haiqiu Yu Dawei Wang 《Agricultural Sciences》 2014年第14期1440-1447,共8页
Application of nitrogen (N) fertilizer is one of the most important approaches on improving maize grain yield. However, as is known to all, overuse N fertilizer not only leads to decline of N use efficiency and maize ... Application of nitrogen (N) fertilizer is one of the most important approaches on improving maize grain yield. However, as is known to all, overuse N fertilizer not only leads to decline of N use efficiency and maize yield, but also leads to potential risk to environment pollution. This experiment was conducted to determine the effects of N fertilizer applications with nine different treatments on soil physical-chemical characters and maize grain yield using hybrid variety Zhengdan 958 in 2011 and 2012. Results indicated that the soil bulk densities of T2 (CK) and T1 were the lowest compared to other treatments in 2011 and 2012, respectively, whereas the soil bulk density of T5 in 2011 and T3 in 2012 were higher than other treatments. The soil porosity and field capacity of T5 in 2011 and T3 in 2012 were lower than other treatments, but those of CK in 2011 and T1 in 2012 were higher than other treatments. The pH values of T3 to T7 were lower than other treatments. These results indicated that the soil bulk densities were increased, whereas the soil porosity, field capacity and values pH were decreased by N application at different stages. N application could increase the N contents of leaf and stem, whereas less or excess N application should not significant improve maize yield. Although the soil organic matter and total N contents of T3 were the highest in both 2011 and 2012, the yield of T4 is the highest in both 2011 and 2012. The application amount, period and times of N fertilizer were important to maize yield. 展开更多
关键词 MAIZE N Fertilizer application YIELD Soil physical and Chemical properties N Content
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Research and Discussion on Physical and Chemical Properties of Cultivating Substrate with Facilities 被引量:1
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作者 MA Ying1 YIN Shulian1 ZHANG Yongxin2 1. Department of Garden in Hebei Professional College of Political Science and Law, Shijiazhuang 050061, P. R . China 2. Flower management centre in Hebei Province Forestry Bureau, Shijiazhuang 050061, P. R. China 《Chinese Forestry Science and Technology》 2008年第2期49-55,共7页
This article, by comparing the basic concepts of substrate and soil, their composition of substance and methods of measuring the indexes of physical and chemical properties, analyzes and researches ways of choosing su... This article, by comparing the basic concepts of substrate and soil, their composition of substance and methods of measuring the indexes of physical and chemical properties, analyzes and researches ways of choosing substrate for cultivation with facilities. It indicates that the normal physical and chemical indexes of evaluating a substrate are bulk density, total porosity, non-capillary porosity, ratio of big porosity to small porosity, the pH and the electrical conductivity (EC) value of the substrate. By measuring the physical and chemical properties of the substrate in different prescription and the cultivation experiments, the best substrate can be sieved. 展开更多
关键词 cultivating with facilities SUBSTRATE SIEVE physical and chemical properties application
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Study on the physical properties and chemical compositions of artificially synthesized coral hydroxyl apatite (CHA) bone
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作者 LI Zhaolin LI Wen +2 位作者 BO Zunzhao YIN Qingshui ZHANG Yu 《Chinese Journal Of Geochemistry》 EI CAS 2009年第4期421-426,共6页
To develop synthesized coralline hydroxyl apatite (CHA) bone graftsubstitute and measure its physical and chemical characteristics. Methods: The CHA bone graft substitute was synthesized from natural mineral―corallin... To develop synthesized coralline hydroxyl apatite (CHA) bone graftsubstitute and measure its physical and chemical characteristics. Methods: The CHA bone graft substitute was synthesized from natural mineral―coralline through hydrothermal exchange process. This process was designed and developed independently by the authors. Its physical and chemical characteristics have been determined and studied using various techniques including Scanning Electron Microscopy (SEM), electron microscope image processing, scanning electron microscope energy spectrography; chemical analysis, ICP-AES, X-ray diffraction, etc. Clinical trials have been conducted. Results: Independently developed CHA bone graft-substitute is white in color; its porosity is 25.87%–53.58%, which is approximate to that of human bones and original coral. It is larger than 3–4 in hardness by Mohs hardness scale and the compressive strength ranges from 4.87 to 12.31 MPa. The chemical compositions of the CHA are 53.13%–64.09% CaO and 35.52%–46.48% P2O5. CaO/P2O5 is 1.143–1.804. ICP-AES analysis detected twenty-four trace elements including Pb, Co, Ni, Ba, Mn, Cr, Th, V, Cu, Ti, K, Mo, Zn, Mg, Nb, Be, Sc, Al, Sr, Na, Li, etc. Ca, P, K, Na, Al and Sr are relatively high while the rest are less than n–n×10-6, which is acceptable by human body. The REE level in the CHA bone measured by ICP-MS is 1.433×10-9–2.212×10-9, which is within the acceptable range for human beings. Conclusions: The process of synthesized CHA bone graft-substitute is an innovated independently developed method and concept. Its color, porosity and chemical composition are similar to those of human bones; therefore it has very good biocompatibility and excellent conductivity. Sixty clinical cases have proved that CHA bone graft-substitute has a strong bone-forming ability, no toxicity, no side effect, and better sacralization. It is a fine substitute for bone transplantation. 展开更多
关键词 羟基磷灰石 化学成分 人工合成 物理特性 珊瑚
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Facies-constrained prestack seismic probabilistic inversion driven by rock physics 被引量:4
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作者 Kun LI Xingyao YIN Zhaoyun ZONG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2020年第6期822-840,共19页
Seismic Rock physics plays a bridge role between the rock moduli and physical properties of the hydrocarbon reservoirs.Prestack seismic inversion is an important method for the quantitative characterization of elastic... Seismic Rock physics plays a bridge role between the rock moduli and physical properties of the hydrocarbon reservoirs.Prestack seismic inversion is an important method for the quantitative characterization of elasticity,physical properties,lithology and fluid properties of subsurface reservoirs.In this paper,a high order approximation of rock physics model for clastic rocks is established and one seismic AVO reflection equation characterized by the high order approximation(Jacobian and Hessian matrix)of rock moduli is derived.Besides,the contribution of porosity,shale content and fluid saturation to AVO reflectivity is analyzed.The feasibility of the proposed AVO equation is discussed in the direct estimation of rock physical properties.On the basis of this,one probabilistic AVO inversion based on differential evolution-Markov chain Monte Carlo stochastic model is proposed on the premise that the model parameters obey Gaussian mixture probability prior model.The stochastic model has both the global optimization characteristics of the differential evolution algorithm and the uncertainty analysis ability of Markov chain Monte Carlo model.Through the cross parallel of multiple Markov chains,multiple stochastic solutions of the model parameters can be obtained simultaneously,and the posterior probability density distribution of the model parameters can be simulated effectively.The posterior mean is treated as the optimal solution of the model to be inverted.Besides,the variance and confidence interval are utilized to evaluate the uncertainties of the estimated results,so as to realize the simultaneous estimation of reservoir elasticity,physical properties,discrete lithofacies and dry rock skeleton.The validity of the proposed approach is verified by theoretical tests and one real application case in eastern China. 展开更多
关键词 Prestack seismic inversion Seismic rock physics physical properties estimation Bayesian inference Probabilistic mixture model Markov chain Monte Carlo
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Two-Dimensional Terahertz Time-Domain Spectroscopy and Its Applications 被引量:1
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作者 Jia-Yu Zhao Wei-Wei Liu 《Journal of Electronic Science and Technology》 CAS CSCD 2015年第1期6-13,共8页
In this work, we review the developing progress of two-dimensional terahertz time-domain spectroscopy(THz-TDS) and its diverse applications, including analyzing the polarization of THz radiation from a laser-induced... In this work, we review the developing progress of two-dimensional terahertz time-domain spectroscopy(THz-TDS) and its diverse applications, including analyzing the polarization of THz radiation from a laser-induced plasma source and studying the corresponding physical mechanism, and characterizing the optical properties of crystals, etc. 展开更多
关键词 application laser-induced plasma optical property physical mechanism POLARIZATION two-dimensional terahertz time-domain spectros
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Production Benefits of Double-Cropping Rice Under Optimized Application of Nitrogen and Potassium Fertilizers Combined with Chinese Milk Vetch and Straw Co-Returning to Fields 被引量:3
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作者 DONG Chun-hua MA Chao-hong +4 位作者 HU Ke-xin HE Yun-long LI Wan-min CHU Fei YANG Zeng-ping 《Agricultural Science & Technology》 CAS 2021年第1期17-25,共9页
In order to explore the technology and effects of reducing nitrogen and potassium fertilizer applications in double-cropping rice,a field plot experiment was conducted to study the effects of optimized application of ... In order to explore the technology and effects of reducing nitrogen and potassium fertilizer applications in double-cropping rice,a field plot experiment was conducted to study the effects of optimized application of nitrogen and potassium fertilizers combined with returning Chinese milk vetch and straw to fields on yield,fertilizer utilization efficiency,net photosynthetic rate(Pn),stomatal conductance(Gs),intercellular CO_(2) concentration(Ci),chlorophyll content(SPAD value)and soil physical and chemical properties in late rice harvest period.The results showed that the optimized application of nitrogen and potassium fertilizers combined with the integrated technology of Chinese milk vetch and straw co-returning to the field could enhance the photosynthetic efficiency of double-cropping rice,increase rice yield,and enhance soil biological activity,especially T4 treatment involving the returning of Chinese milk vetch and straw to the field instead of 30%nitrogen fertilizer achieved the highest rice yield,fertilizer use efficiency,net photosynthetic rate and soil biological activity.Compared with the conventional fertilization treatment T2,the total rice yield of T4 treatment increased by 4.1%,among which the early rice and late rice increased by 6.3%and 2.4%,respectively;Pn,Gs and SPAD values of flag leaves at full heading stage significantly increased,and the contents of soil active organic carbon,alkali hydrolyzed nitrogen,available phosphorus and readily available potassium significantly increased. 展开更多
关键词 Double-cropping rice Optimized application of nitrogen and potassium fertilizers Chinese milk vetch and straw co-returning to fields Rice yield Soil physical and chemical properties
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Application of Biochemical Fulvic Acid Potassium in Transplantation of Trees 被引量:1
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作者 Yang Qunhui He Xiang +6 位作者 Bi Yunqing Yang Peiwen Zhang Qing Yang Mingying Shi Zhufeng Peng Rongzhen Wang Jiayin 《Plant Diseases and Pests》 CAS 2020年第2期16-19,共4页
[Objective]The paper was to clarify the application of biochemical fulvic acid potassium on the survival rate and growth of various trees transplanted in the process of landscaping.[Method]Two experimental treatments(... [Objective]The paper was to clarify the application of biochemical fulvic acid potassium on the survival rate and growth of various trees transplanted in the process of landscaping.[Method]Two experimental treatments(i.e.decomposed organic fertilizer+biochemical fulvic acid potassium water soluble fertilizer,decomposed organic fertilizer+compound fertilizer)were designed to determine the changes in physical and chemical properties before and after soil treatment,and the survival rate,plant height and ground diameter of four different cultivated plants within one year,and the effects of applying biochemical fulvic acid potassium on cultivated plants were investigated.[Result]The soil organic matter,total nitrogen,alkali-hydrolyzable nitrogen,soil available phosphorus,soil available potassium and p H value in the soil treated with decomposed organic fertilizer+biochemical fulvic acid potassium soluble fertilizer,and decomposed organic fertilizer+compound fertilizer increased significantly,and the soil bulk density decreased obviously.The survival rates,plant heights and ground diameters of four different cultivated plants were significantly improved after application of decomposed organic fertilizer+biochemical fulvic acid potassium water soluble fertilizer,and decomposed organic fer-tilizer+compound fertilizer(P<0.05).[Conclusion]The application of biochemical fulvic acid potassium on cultivated plants effectively improved soil fertility,increased the utilization of nitrogen,phosphorus and potassium,improved the growth of plants,and promoted the growth of landscaping plants after transplantation. 展开更多
关键词 Biochemical fulvic acid potassium TRANSPLANTATION physical and chemical properties application
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The Reality and Application of Yin and Yang
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作者 Wutong Song Hongxin Cao 《Chinese Medicine》 CAS 2022年第2期23-31,共9页
Ancient Chinese philosophers discovered Yin and Yang and the laws of Yin and Yang movement during their exploration and practice of nature more than two thousand years ago, and applied them to life, science, philosoph... Ancient Chinese philosophers discovered Yin and Yang and the laws of Yin and Yang movement during their exploration and practice of nature more than two thousand years ago, and applied them to life, science, philosophy and medicine, playing an important role in the achievement of ancient Chinese civilization. Through historical changes, yin and yang have gradually been regarded as a concept or theory, thus making it difficult for people to understand the connotation of Yin-Yang and make new discoveries and progress. Nowadays, many scholars in China and the West are interested in studying the treasures of ancient Chinese civilization. We illustrate the actual function of Yin and Yang by explaining the essential state of matter, the law of physical movement, the transformation of energy, and then illustrate the practical application in life and science. In conclusion, yin-yang is a key to unlocking the treasures of traditional Chinese civilization, which can help to bring into play its original values, and continue to provide new insights and directions for the development of modern science and the advancement of humanities. 展开更多
关键词 Yin and Yang Material properties physical Movement Energy Transformation Practical applications
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Recent progress in molten salt synthesis of low-dimensional perovskite oxide nanostructures, structural characterization,properties, and functional applications: A review 被引量:4
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作者 Piaojie Xue Heng Wu +1 位作者 Yao Lu Xinhua Zhu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2018年第6期914-930,共17页
Molten salt synthesis (MSS) method has advantages of the simplicity in the process equipment, versatile and large-scale synthesis, and friendly environment, which provides an excellent approach to synthesize high pu... Molten salt synthesis (MSS) method has advantages of the simplicity in the process equipment, versatile and large-scale synthesis, and friendly environment, which provides an excellent approach to synthesize high pure oxide powders with controllable compositions and morphologies. Among these oxides, perovskite oxides with a composition of ABO3 exhibit a broad spectrum of physical properties and functions (e.g. ferroelectric, piezoelectric, magnetic, photovoltaic and photocatalytic properties). The downscaling of the spatial geometry of perovskite oxides into nanometers result in novel properties that are different from the bulk and film counterparts. Recent interest in nanoscience and nanotechnology has led to great efforts focusing on the synthesis of low-dimensional perovskite oxide nanostructures (PONs) to better understand their novel physical properties at nanoscale. Therefore, the low-dimensional PONs such as perovskite nanoparticles, nanowires, nanorods, nanotubes, nanofibers, nanobelts, and two dimensional oxide nanostructures, play an important role in developing the next generation of oxide electronics. In the past few years, much effort has been made on the synthesis of PONs by MSS method and their structural characterizations. The functional applications of PONs are also explored in the fields of storage memory, energy harvesting, and solar energy conversion. This review summarizes the recent progress in the synthesis of low-dimensional PONs by MSS method and its modified ways. Their structural char- acterization and physical properties are also scrutinized. The potential applications of low-dimensional PONs in different fields such as data memory and storage, energy harvesting, solar energy conversion, are highlighted. Perspectives concerning the future research trends and challenges of low-dimensional PONs are also outlined. ~ 2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology. 展开更多
关键词 Low-dimensional perovskite nanostructures Molten salt synthesis Structural characterization physical properties Functional applications
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聚合物修饰黑磷及黑磷类似物纳米材料在生物医学中的应用进展
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作者 苏澳旗 李欣昱 +2 位作者 王冉 高丽丽 焦体峰 《化学进展》 北大核心 2025年第2期133-156,共24页
在二维纳米材料中,黑磷(BP)被认为是弥补石墨烯和TMD缺点的有希望的候选材料,而低维黑磷是一类由层状半导体BP衍生出的纳米材料。其中BP具有结构的高度各向异性、带隙宽度可调、空穴迁移率和电子迁移率高等特点,这些特点给予BP独特的性... 在二维纳米材料中,黑磷(BP)被认为是弥补石墨烯和TMD缺点的有希望的候选材料,而低维黑磷是一类由层状半导体BP衍生出的纳米材料。其中BP具有结构的高度各向异性、带隙宽度可调、空穴迁移率和电子迁移率高等特点,这些特点给予BP独特的性质,如导电性、光热、光动力学、力学行为等,BP的近红外光响应使其在光热/光动力抗菌中显示出显著效果。此外,由于其独特的层状结构,BPNS具有高的表面积与体积比,这使其成为负载和递送其他抗菌纳米材料或药物的优良药物载体。本文首先讨论了低维BP的物理特性并介绍了不同的制备方法,然后系统梳理聚合物修饰黑磷纳米材料在各个领域的治疗应用进展,如癌症治疗(光疗,药物输送和协同免疫治疗)、骨再生和神经发生,最后讨论了未来临床试验面临的一些挑战和进一步研究的可能方向。 展开更多
关键词 低维黑磷 生物成像 物理性质 生物医学应用
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重晶石粉物理性能检测在化工中的应用与优化研究
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作者 王琦 《化工管理》 2025年第6期61-64,共4页
文章对重晶石粉的物理性能检测在化工领域中的应用进行了研究,对重晶石粉的密度、碱土金属含量、筛余和黏度效应等检测方法进行了探讨,介绍了当前检测重晶石粉物理性能的主要方法,提出了优化检测精度与效率的方案,对重晶石粉物理性能的... 文章对重晶石粉的物理性能检测在化工领域中的应用进行了研究,对重晶石粉的密度、碱土金属含量、筛余和黏度效应等检测方法进行了探讨,介绍了当前检测重晶石粉物理性能的主要方法,提出了优化检测精度与效率的方案,对重晶石粉物理性能的先进检测技术、误差控制以及新型测试方法进行了深入探讨。文章旨在优化检测手段,提升重晶石粉在化工领域的应用效果,为相关生产工艺的改进提供技术支持。 展开更多
关键词 重晶石粉 物理性能检测 化工应用 检测优化
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乙苯脱氢制苯乙烯反应过程专用模拟系统开发
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作者 陈玉石 赵芳磊 +2 位作者 王建平 孙晓岩 项曙光 《化学工程》 CAS CSCD 北大核心 2024年第10期83-88,共6页
为了实现对乙苯脱氢制苯乙烯反应过程的准确模拟计算,采用MySQL数据库软件建立专用物性数据库,构建等温积分动力学反应器计算模型,基于Cape-Open标准和C++语言,建立苯乙烯反应器模块,并集成到通用流程模拟软件中,形成乙苯脱氢制苯乙烯... 为了实现对乙苯脱氢制苯乙烯反应过程的准确模拟计算,采用MySQL数据库软件建立专用物性数据库,构建等温积分动力学反应器计算模型,基于Cape-Open标准和C++语言,建立苯乙烯反应器模块,并集成到通用流程模拟软件中,形成乙苯脱氢制苯乙烯反应过程的专用模拟系统。采用工厂数据对所开发的模拟系统进行检验,并将计算值与实际值进行对比。结果表明:计算结果与工艺数据基本一致,产品组成、反应器温降和压降的模拟值与实际值的相对偏差都在1%以内,说明开发的专用反应过程模拟系统可进行较为准确的模拟计算。 展开更多
关键词 乙苯脱氢 物性数据库 反应器模块 系统开发
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长期不同施氮量下黑土团聚体稳定性及有机碳含量的变化 被引量:9
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作者 姚俊红 武俊男 +4 位作者 王呈玉 崔炎田 高云航 孙嘉璐 刘淑霞 《农业环境科学学报》 CAS CSCD 北大核心 2024年第1期102-110,共9页
为测定不同氮肥施用量对黑土团聚体组成及稳定性、有机碳含量及团聚体有机碳分布的影响,阐明黑土有机碳稳定性对不同施氮水平的响应机制,本研究在吉林省梨树县不同施氮水平长期定位试验田进行取样,以施氮水平不同设置5个处理,分别为T1(0... 为测定不同氮肥施用量对黑土团聚体组成及稳定性、有机碳含量及团聚体有机碳分布的影响,阐明黑土有机碳稳定性对不同施氮水平的响应机制,本研究在吉林省梨树县不同施氮水平长期定位试验田进行取样,以施氮水平不同设置5个处理,分别为T1(0)、T2(160 kg·hm^(-2))、T3(240 kg·hm^(-2))、T4(280 kg·hm^(-2))、T5(320 kg·hm^(-2)),分析长期不同施氮量下水稳性团聚体组成、团聚体结构特征、土壤总有机碳含量及团聚体有机碳分布的变化,探究酸化黑土有机碳含量影响特征。结果表明:随氮肥施用水平的升高,土壤碱解氮(AN)和全氮(TN)含量先增后减,T3处理含量最高,AN和TN分别比T1处理高24.90%、10.28%;土壤速效磷(AP)的含量呈下降趋势。随氮肥用量的提高,土壤团聚体呈现大粒径团聚体向小粒径团聚体转变的趋势,>2 mm粒径团聚体下降14.55%。土壤有机碳总量随施氮水平的提高呈先增后减的趋势,施氮量为280 kg·hm^(-2)有机碳含量最高;>2 mm和2~0.25 mm粒径团聚体有机碳含量较高;不同施氮水平下有机碳含量与团聚体稳定性特征的几何平均直径、土壤团聚体破坏率、不稳定团粒指数和土壤化学性质的相关度较高。研究表明:通过13 a连续施入不同水平氮肥,土壤有机碳含量随氮肥施用量的增加呈先增后减的趋势;氮肥施用量增加会显著降低土壤pH,土壤团聚体有机碳主要分布在2~0.25 mm粒径中。 展开更多
关键词 氮肥施用量 黑土 土壤理化性质 团聚体有机碳 团聚体稳定性
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异麦芽酮糖研究进展及其在食品加工中的应用 被引量:2
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作者 周泽玉 康淞皓 +3 位作者 车会莲 孙丽娟 叶丽容 吴广枫 《现代食品科技》 CAS 北大核心 2024年第7期379-392,共14页
异麦芽酮糖作为功能性代糖,风味和理化性质与蔗糖相似,在抗酸、微生物发酵和晶体结构方面稳定,吸湿性和溶解性相对较低,适合应用于不同的食品配方。经大量研究证明,其安全性和耐受性在亚慢性毒性、胚胎毒性、致突变性和人体研究等方面... 异麦芽酮糖作为功能性代糖,风味和理化性质与蔗糖相似,在抗酸、微生物发酵和晶体结构方面稳定,吸湿性和溶解性相对较低,适合应用于不同的食品配方。经大量研究证明,其安全性和耐受性在亚慢性毒性、胚胎毒性、致突变性和人体研究等方面都有所保障。国内外异麦芽酮糖的生产方式主要为操作稳定可重复的固定化微生物转化或显著催化的固定化酶转化,通过重结晶来提纯,利用高效液相色谱定量检测。其具有血糖指数低、消化吸收速度相对缓慢、改善胰岛素反应、益生元特性、低致龋潜力、调节肠道菌群等健康功效,在特殊医学用途食品(FSMP)、儿童食品、普通食品(包括乳制品、谷物制品等)、营养运动食品中都有深入研究和实际应用,该文还结合现有监管政策提出重新梳理其食品添加剂和新食品原料双重身份的建议。 展开更多
关键词 异麦芽酮糖 理化性质 安全性 制备检测 健康功效 应用分析
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甘露聚糖的理化特性、制备、测定和代谢途径及其应用的研究进展 被引量:1
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作者 王子源 李浩然 +4 位作者 甄玉国 王涛 张学峰 秦贵信 孙喆 《饲料工业》 CAS 北大核心 2024年第13期23-30,共8页
甘露聚糖是一种天然的多糖物质,广泛分布于酵母菌、植物组织中。甘露聚糖作为饲料添加剂能够增强动物体液免疫和细胞免疫的能力,保持肠道微生态平衡并改善瘤胃功能。文章分别对甘露聚糖的理化特性、制备、测定和代谢途径及其应用进行了... 甘露聚糖是一种天然的多糖物质,广泛分布于酵母菌、植物组织中。甘露聚糖作为饲料添加剂能够增强动物体液免疫和细胞免疫的能力,保持肠道微生态平衡并改善瘤胃功能。文章分别对甘露聚糖的理化特性、制备、测定和代谢途径及其应用进行了归纳和总结,以期为甘露聚糖的开发应用提供参考价值。 展开更多
关键词 甘露聚糖 理化特性 制备方法 测定方法 代谢途径 应用
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茶多酚的功能活性及稳态化研究进展 被引量:2
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作者 陈俊婕 劳颖仪 +8 位作者 陈晓维 余元善 温靖 吴继军 徐玉娟 肖更生 杨继国 唐延天 胡腾根 《中国果菜》 2024年第8期25-31,共7页
茶作为我国历史悠久且最具代表性的传统饮品,是中华民族文化的重要载体。茶多酚是茶叶中主要的生物活性成分之一,具有多种理化性质,在食品、医药、化妆品等多个领域具有广泛的应用前景。然而,在茶多酚使用过程中,活性易受光照、氧气和... 茶作为我国历史悠久且最具代表性的传统饮品,是中华民族文化的重要载体。茶多酚是茶叶中主要的生物活性成分之一,具有多种理化性质,在食品、医药、化妆品等多个领域具有广泛的应用前景。然而,在茶多酚使用过程中,活性易受光照、氧气和高温等外界条件的影响,极大地限制了其在工业上的应用。本文总结了茶多酚的理化性质和功能应用;概述了目前常见的茶多酚稳态化技术即包埋,通过稳态化技术将茶多酚有效地包埋在特定的载体中,有利于茶多酚更好地发挥效用,显著提高其稳定性,从而拓展其应用场景,为茶多酚的深入研究和应用提供参考。 展开更多
关键词 茶多酚 理化性质 应用 稳态化包埋
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中国多元林草原料生物质资源分布及醇类利用指标分析 被引量:1
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作者 王浩 王昱 +3 位作者 李金平 雷廷宙 田苗 李能安 《农业工程学报》 EI CAS CSCD 北大核心 2024年第6期298-308,共11页
中国林草原料资源丰富,对其分布的整理不仅有助于推动林草原料的综合利用,也有助于解决林草废弃物带来的环境问题。因此,该研究根据中国大陆地区的地理经纬度,对全国范围内的代表性林草原料进行了分区梳理,并筛选出了各地区的优势林草... 中国林草原料资源丰富,对其分布的整理不仅有助于推动林草原料的综合利用,也有助于解决林草废弃物带来的环境问题。因此,该研究根据中国大陆地区的地理经纬度,对全国范围内的代表性林草原料进行了分区梳理,并筛选出了各地区的优势林草作物。对多元林草原料的分布与组成特性,水分、挥发分、纤维素含量、半纤维素含量、C元素含量、O元素含量、热值等进行了共性和个性指标的整理,确定了多元林草原料组成与结构分析的数据库检索字段。华东地区甜菜并不适宜作为生物质醇类利用中林草原料,氧元素含量较其他林草原料高出46%,玉米秸秆和水稻秸秆中O元素含量较低,适宜作为生物质醇类利用中林草原料;大豆中纤维素含量明显较低,比其他林草原料低40%,西南地区玉米秸秆高于其他林草原料;西北地区黑麦草和华东地区华南地区甘蔗的比热容值较高,在3.2~4.8 J/(kg·K),其他能源草比热容值多处于0.8~2.4 J/(kg·K)。深入分析各地区代表性林草原料作为醇类利用的指标,探讨多元林草原料的物理性质、化学组成、工业组成、元素组成以及醇类利用潜力的差异性、变异性和相关性。该研究为中国多元林草醇类利用提供了重要的基础支撑和数据参考。 展开更多
关键词 醇类 利用 多元林草 数据库 理化特性
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凹凸棒石的研究与应用发展现状 被引量:1
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作者 孙祥云 梁龙 +1 位作者 谢广元 彭耀丽 《矿产综合利用》 CAS 2024年第5期111-118,132,共9页
这是一篇陶瓷及复合材料领域的论文。凹凸棒石是一种利用价值较高的重要矿产资源,广泛应用于农业、环境、材料、化工、生物、催化等领域,在我国储量丰富,有较好的开发前景。目前对凹凸棒石的利用率还较低,大量的凹凸棒石并未被有效开发... 这是一篇陶瓷及复合材料领域的论文。凹凸棒石是一种利用价值较高的重要矿产资源,广泛应用于农业、环境、材料、化工、生物、催化等领域,在我国储量丰富,有较好的开发前景。目前对凹凸棒石的利用率还较低,大量的凹凸棒石并未被有效开发。本文对国内外凹凸棒石分离提纯与应用现状进行了分析与总结,简述了凹凸棒石的矿物学特征与晶体结构特性;总结了凹凸棒石的成因类型,资源分布,矿产储量,矿石类型,理化性质;归纳了凹凸棒石分离与提纯的研究现状,凹凸棒石表面改性的方法与研究进展,凹凸棒石在矿物功能材料方面的应用状况,在当前研究内容的基础上,分析目前研究过程中出现的问题,提出凹凸棒石研究与应用的新思路与方向。 展开更多
关键词 陶瓷及复合材料 凹凸棒石 理化性质 分离提纯 表面改性 应用发展
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