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Establishment and verification of prediction models for evaluating the Physical and chemical properties of soilless substrates

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International Journal of Agricultural and Biological Engineering 2021年第2期14卷 9-18页

作者： Binbin Gong Ning Wang Tiejun Zhang Shao Li Xiaolei Wu Jing Tian Jingrui Li Guiyun Lyu Hongbo Gao College of Horticulture Hebei Agricultural UniversityBaoding 071001HebeiChina Modern Education Technology Center Hebei Agricultural UniversityBaoding 071001HebeiChina Academy of Agricultural Planning and Engineering MARABeijing 100125China

In soilless culture,a suitable mixed substrate that provides a balanced and stable rhizosphere environment is vital for promoting plant growth.The present study was undertaken to establish seven prediction models of Physical and chemical properties,including bulk density(DB),total porosity(TP),water-holding porosity(WHP),air porosity(AP),WHP/AP,electrical conductivity(EC)and cation exchange capacity(CEC)of mixed substrate based on regression equations of measured values from 76 substrate combinations.These seven models were verified using the measured values of 12 mixed substrates,and the average relative prediction errors(REs)were all less than 10%.A comprehensive property prediction model was established by weighted summation of the seven models of Physical and chemical properties.According to the set values of DB,TP,WHP,AP,WHP/AP,EC and CEC,the comprehensive property model predicted the six mixture proportions of mixed-substrate,as verified using the measured values.This study is the first to establish prediction models for the Physical and chemical properties of mixed substrates.The comprehensive property model could be used to evaluate the Physical and chemical properties of commercial mixed substrates,and to provide the optimal mixture substrate formulations according to the setting property value of production requirement.

关键词： prediction model mixed substrate Physical and chemical properties multiple regressions genetic algorithm

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Classification and comparison of Physical and chemical properties of corn stalk from three regions in China

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International Journal of Agricultural and Biological Engineering 2014年第6期7卷 98-106页

作者： Wang Lu Liu Ronghou Sun Chen Cai Wenfei Tao Yiwei Yin Renzhan Mei Yuanfei Biomass Energy Engineering Research Center School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Urban Agriculture(South) Ministry of AgricultureShanghai 200240China

Corn stalk samples from Anhui,Jiangxi and Shanghai were used as test materials.Their physical,chemical and thermo-chemical engineering characteristics were analyzed.The similarities and differences in properties of corn stalk from the three regions were determined using SIMCA-P and SPSS software in order to obtain a proper energy utilization method of corn stalk.The results show that the corn stalk from Shanghai has significant differences from the samples of Jiangxi and Anhui.In particular,the following properties of corn stalk from Shanghai such as the contents of cellulose,calcium(Ca),iron(Fe),crude ash,volatile matter,carbon(C),nitrogen(N),and oxygen(O)are significantly different from those of Jiangxi and Anhui samples(Pproperties such as the contents of magnesium(Mg),copper(Cu),zinc(Zn),moisture,hydrogen(H),and sulfur(S)have no significant difference among samples of three regions.Compared with the corn stalk in Anhui and Jiangxi,the Shanghai samples are more suitable for the production of ethanol because of their higher ratio of cellulose to hemi-cellulose content.Because of its high content of ash and low calorific value,the Shanghai corn stalk is suitable for the gasification process instead of for direct combustion or bio-oil production.The research can provide a reference for raw material selection for biomass energy production and utilization.

关键词： corn stalk Physical and chemical properties bioenergy principal components analysis partial least squares discriminant analysis

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Selected Physical and chemical properties of mechanically extracted neem seed oil sourced as a preservative for ligno-cellulose in south-western Nigeria

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Forestry Studies in China 2011年第4期13卷 263-269页

作者： Andrew A. ERAKHRUMEN Department of Forest Resources Management Faculty of Agriculture and Forestry University of Ibadan Ibadan Nigeria

Most of the seeds produced by neem （Azadirachta indica A. Juss） trees in Nigeria are currently underutilized. Hence, relevant literature provides only limited information conceming many of the seed oils from this country, especially where it concems the potential applications of these oils as preservatives for ligno-cellulose against bio-deterioration. Using standard procedures therefore, this study was carried out to evaluate and document selected Physical and chemical properties of neem seed oil （NSO）, mechanically extracted using a cold press at 31.03 N-mm^-2 pressure and a room temperature of 25 ± 2℃. The results show that oil yield was 38.42% with a specific gravity of 0.91 ± 0.01. The amount of acid was 18.24 ± 1.31 mg KOH.g^-1 and that of iodine 93.12 ± 2.01 g-100 g^- 1, while saponification and peroxide values were 172.88 ± 2.06 and 1.42 ± 0.04 mg·g^-1 respectively. The implication of the values obtained, particularly those for the chemical properties, as they concern the potential application of NSO as a preservative for ligno-eellulose, is likely that it may be useful in this regard since the values may support some of the documented anti-microbial properties of the oil, although other Physical and chemical properties that may affect this potential are recommended for investigations. Conclusions and other recommendations follow in line with the results of the study.

关键词： neem seed oil Physical and chemical properties mechanical extraction cold press

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Physical and chemical properties of yak butter

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中国甜菜糖业 2015年第4期 46-50页

作者： SUN Meiqing MA Ying School of Food Science and Engineering Harbin Institute of technology Harbin 150090 China

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Research and Discussion on Physical and chemical properties of Cultivating Substrate with Facilities

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Chinese Forestry Science and Technology 2008年第2期7卷 49-55页

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

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.

关键词： cultivating with facilities substrate sieve Physical and chemical properties application

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掺钒电解二氧化锰的放电特性及其某些理化性能(Ⅰ)

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福建师范大学学报(自然科学版) 1987年第1期 32-38页

作者：王家雄朱则善张其昕福建师范大学化学系电化学研究室

掺钒电解二氧化锰（EMD-V）样品是在合有VOSO;的H;SO;-MnSO;溶液中通过阳极氧化制备的。EMD-V样品在中性NH;Cl-ZnCI;电解质中的放电性能优于未掺杂EMD样品。X射线衍射图表明,EMD-V样品属于γ型MnO;,具有纤维态结构。X射线光电子能谱分... 详细信息

掺钒电解二氧化锰（EMD-V）样品是在合有VOSO;的H;SO;-MnSO;溶液中通过阳极氧化制备的。EMD-V样品在中性NH;Cl-ZnCI;电解质中的放电性能优于未掺杂EMD样品。X射线衍射图表明,EMD-V样品属于γ型MnO;,具有纤维态结构。X射线光电子能谱分析表明,钒在EMD-V样品中以V;O;的形式存在。

关键词： Electrolytic Manganese Dioxide Doped with Vanadium Discharge Character Physical and chemical properties

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Size,shape,charge and“stealthy”surface:Carrier properties affect the drug circulation time in vivo

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Asian Journal of Pharmaceutical Sciences 2021年第4期16卷 444-458页

作者： Jinwei Di Xiang Gao Yimeng Du Hui Zhang Jing Gao Aiping Zheng State Key Laboratory of Toxicology and Medical Countermeasures Beijing Institute of Pharmacology and ToxicologyBeijing 100850China

The present review sets out to discuss recent developments of the effects and mechanisms of carrier properties on their circulation time.For most drugs,sufficient in vivo circulation time is the basis of high bioavailability.Drug carrier plays an irreplaceable role in helping drug avoid being quickly recognized and cleared by mononuclear phagocyte system,to give drug enough time to arrive at targeted organ and tissue to play its therapeutic effect.The Physical and chemical properties of drug carriers,such as size,shape,surface charge and surface modification,would affect their in vivo circulation time,metabolic behavior and biodistribution.The final circulation time of carriers is determined by the balance between macrophage recognitions,blood vessel penetration and urine excretion.Therefore,when designing the drug delivery system,we should pay much attention to the properties of drug carriers to get enough in vivo circulation time to arrive at target site eventually.This article mainly reviews the effect of carrier size,size,surface charge and surface properties on its circulation time in vivo,and discusses the mechanism of these properties affecting circulation time.This review has reference significance for the research of long-circulation drug delivery system.

关键词： Drug carrier Circulation time Physical and chemical properties Macrophages Phagocytosis

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Extended wet sieving method for determination of complete particle size distribution of general soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 242-257页

作者： Shengnan Ma Yi Song Jiawei Liu Xingyu Kang Zhongqi Quentin Yue Department of Civil Engineering The University of Hong KongHong KongChina

The traditional standard wet sieving method uses steel sieves with aperture?0.063 mm and can only determine the particle size distribution(PSD)of gravel and sand in general soil.This paper extends the traditional method and presents an extended wet sieving method.The extended method uses both the steel sieves and the nylon filter cloth sieves.The apertures of the cloth sieves are smaller than 0.063 mm and equal 0.048 mm,0.038 mm,0.014 mm,0.012 mm,0.0063 mm,0.004 mm,0.003 mm,0.002 mm,and 0.001 mm,respectively.The extended method uses five steps to separate the general soil into many material sub-groups of gravel,sand,silt and clay with known particle size ranges.The complete PSD of the general soil is then calculated from the dry masses of the individual material sub-groups.The extended method is demonstrated with a general soil of completely decomposed granite(CDG)in Hong Kong,China.The silt and clay materials with different particle size ranges are further examined,checked and verified using stereomicroscopic observation,physical and chemical property tests.The results further confirm the correctness of the extended wet sieving method.

关键词： Particle size distribution(PSD) General soil Silt Clay Wet sieving Physical and chemical properties

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Pyraclostrobin-loaded poly(lactic-co-glycolic acid) nanospheres: Preparation and characteristics

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Journal of Integrative Agriculture 2018年第8期17卷 1822-1832页

作者： YIN Ming-ming ZHENG Yu CHEN Fu-liang Institute of Plant Protection Chinese Academy of Agricultural SciencesBeijing 100193P.R.China

We used poly(lactic-co-glycolic acid)(PLGA) as a carrier polymer for pyraclostrobin-loaded nanospheres. Using the ultrasound emulsification-solvent evaporation method, the physicochemical characteristics and release properties of the pyraclostrobin-loaded nanospheres were studied by dialysis. The optimal nanospheres prepared had a diameter of 0.6 μm, an active ingredient loading of 17.2%, and a loading rate of 89.7%. Infrared spectroscopy data and differential scanning calorimetry revealed that pyraclostrobin was successfully embedded in the carrier PLGA, and photostability tests indicated enhanced ultraviolet resistance of pyraclostrobin-loaded PLGA nanospheres nanospheres. Release property testing indicated that smaller particles had a faster release rate. Nanospheres also had a faster release rate in slightly acidic and slightly basic environments than in a neutral condition. Agitated nanospheres had a faster release rate than immobile nanospheres. The cumulative release kinetics of pyraclostrobin-loaded nanospheres was consistent with the first order kinetic equation and the Weibull equation.

关键词： nanospheres pyraclostrobin PLGA Physical and chemical properties slow release

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Experimental study on hydration damage mechanism of shale from the Longmaxi Formation in southern Sichuan Basin, China

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Petroleum 2016年第1期2卷 54-60页

作者： Xiangjun Liu Wei Zeng Lixi Liang Jian Xiong State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China

As a serious problem in drilling operation,wellbore instability restricts efficient development of shale gas.The interaction between the drilling fluid and shale with hydration swelling property would have impact on the generation and propagation mechanism of cracks in shale formation,leading to wellbore instability.In order to investigate the influence of the hydration swelling on the crack propagation,mineral components and physicochemical properties of shale from the Lower Silurian Longmaxi Formation(LF)were investigated by using the XRD analysis,cation exchange capabilities(CEC)analysis,and SEM observation,and we researched the hydration mechanism of LF shale.Results show that quartz and clay mineral are dominated in mineral composition,and illite content averaged 67%in clay mineral.Meanwhile,CEC of the LF shale are 94.4 mmol/kg.The process of water intruding inside shale along microcracks was able to be observed through high power microscope,meanwhile,the hydration swelling stress would concentrate at the crack tip.The microcracks would propagate,bifurcate and connect with each other,with increase of water immersing time,and it would ultimately develop into macro-fracture.Moreover,the macrocracks extend and coalesce along the bedding,resulting in the rock failure into blocks.Hydration swelling is one of the major causes that lead to wellbore instability of the LF shale,and therefore improving sealing capacity and inhibition of drilling fluid system is an effective measure to stabilize a borehole.

关键词： Longmaxi Formation shale Hydration Rock failure Physical and chemical properties Micro structure

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