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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 *** most drugs,sufficient in vivo circulation time is the basis of high *** 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 *** 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 *** final circulation time of carriers is determined by the balance between macrophage recognitions,blood vessel penetration and urine ***,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 *** 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 *** 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

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 *** 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 *** 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 *** show that quartz and clay mineral are dominated in mineral composition,and illite content averaged 67%in clay ***,CEC of the LF shale are 94.4 mmol/*** 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 *** microcracks would propagate,bifurcate and connect with each other,with increase of water immersing time,and it would ultimately develop into ***,the macrocracks extend and coalesce along the bedding,resulting in the rock failure into *** 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

A Palladium Based Alloy for Prosthetic Dentistry: Structure and properties

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贵金属 2012年第A1期33卷 269-272页

作者： STEPANOVA Galina PARUNOV Vitaly VASEKIN Vasily KAREVA Maria SINAGEJKINA Julia OJSC "SIC 'Supermetal'" MoscowRussia Moscow State University for Medicine and Dentistry Moscow Russia Lomonosov Moscow State University Moscow Russia.

Using the results of physical and chemical researches and mechanical tests of the Pd-Au-Cu-Sn system alloys, a new palladium-based alloy has been chosen and studied in detail. It has a higher plasticity and a lower hardness than the Palladent alloy, widely used in prosthetic dentistry: its hardness is lower than 300 MPa, and its specific elongation is 10%~14 %. At the same time, such important practical characteristics of the alloys as the strength of adhesion to ceramics and thermal expansion coefficient are almost similar.

关键词： prosthetic dentistry palladium-based alloy physical and chemical properties mechanical tests phase diagram

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

Effects of Biochar with Organic Materials on Substratum for Raising Rice Seedlings

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Agricultural Science & Technology 2016年第5期17卷 1155-1160页

作者：王晓燕方玉凤庞荔丹孟婷婷戴建军东北农业大学资源与环境学院黑龙江哈尔滨150030

[Objective] With a rice variety ＂Long Rice 11＂ as a test cultivar,an experiment of raising rice seedlings with the new substrata prepared from biochar,and maize stalks,rice husks,organic fertilizer,turf,zeolite,fine river sand and arable layer soil by mixing according to certain volume proportions was caried out,in order to investigate the physical and chemical properties of different organic-material seedling-raising substrata and the effects of these substrata on seedling growth.[Method] The experiment raised seedlings in greenhouses and adopted randomized block arrangement.[Result] The substratum of biochar mixed with maize stalks and rice husks could increase the maximum water-holding capacity of the substratum,reduce the volume weight of the substratum and improve the buffering effect of the *** also had great effects on the contents of alkali-hydrolyzale nitrogen and rapidly available potassium in the substratum,and could improve the root number and substantial degree of rice seedlings.[Conclusion] Biochar with maize stalks and rice husks（the treament HC） is the optimal substratum in this study.

关键词： Biochar Rice seedling substrate physical and chemical properties Seedlings growth

Physi-chemical Property Research of Polysaccharides from Pomegranate Flowers

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Agricultural Sciences 2021年第2期12卷 59-67页

作者： Lixin Peng Yizhao Huang Wei Tan Zhiwei Wei Lihua Zhang Zaozhuang University Zaozhuang China International Center for Bamboo and Rattan Beijing China

Pomegranate flowers as row materials were used for extraction of polysaccharides by water-extraction and alcohol-precipitation method. After purification, the physical and chemical properties, structure, monosaccharide composition and molecular weight were studied. The results showed that the polysaccharides from pomegranate flowers mainly contained two kinds of water soluble acidic polysaccharides, and monosaccharide composition were arabinose and galactose, both contained hydroxyl, carboxyl, amino, hydroxyl radical, sulfate, beta glycosidic bond and alpha glycosidic bond structure. The molecular weight of PP1 and PP2 were 6.16 × 104 (±6.6%) and 9.01 × 104 (±3.2%), respectively. The results of this study laid the foundation for further development and application of polysaccharides from pomegranate flowers.

关键词： Polysaccharides Pomegranate Flowers physical and chemical properties

Effects of Different Farming Methods and Their Effects on Soil Physicochemical properties of Guilin Maojian Tea Gardens

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Agricultural Biotechnology 2018年第5期7卷 186-190页

作者： Lingyun ZHANG Shuyi LI Sisi Qin Changjian JIANG Qifa LONG Min SU Chusheng LIU Qianhua WU Guangxi Guilin Tea Research Institute Guilin 541004China

In order to further optimize the cultivation and agronomic technology of Guilin Maojian tea gardens, the effects, efficiencies and costs of different farming methods and their effects on the physiochemical properties of tea garden soil were studied through the modification of the test sites with the non-farming land as the control. The results showed that human farming, mini-tiller farming and crawler tractor farming could improve the physical and chemical properties of soil. After farming, the soil had good water retention but low moisture content compared to the control group, while the soil bulk density and hardness value were significantly lower than those of the control, and the porosity of soil was significantly higher than that of contrast. With the passage of time, soil bulk density and hardness value gradually increased after farming, while the porosity of soil decreased gradually. There were great differences in the effects, efficiencies and costs of different farming methods. Crawler tractor had the best and most stable farming effect, and the operation efficiency was 10 times that of human farming while the cost was only 0.39 times of human farming. Therefore, it was feasible to adopt mini-tiller or crawler tractor to carry out mechanical farming of Guilin Maojian tea garden, which provided theoretical references for the soil property improvement using mechanical farming and was favorable for promoting the popularization of farming machines and the acceleration of mechanization of tea gardens. But for tea plantations that are intended to be mechanized, apart from the mechanical and technical personnel to be configured in place, the site conditions, planting modes and mechanical way reservation of tea garden should be planned accordingly. It is recommended to select flat or gentle slope for reclamation, and preference is given to non-sexual tea tree varieties with big line spacing over 180 cm long. Moreover, the main road construction should be more than

关键词： Guilin Maojian tea Tea garden Farming methods Soil physical and chemical properties

Study on Influencing Factors of Farmland Soil Heavy Metals in Central Yunnan Province

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Agricultural Science & Technology 2013年第4期14卷 645-650页

作者：余小芬陈军彭荣珍邱学礼付斌倪明云南省农业科学院农业环境资源研究所云南昆明650205

[Objective] This study aimed to explore the relationship between contents of heavy metals with soil type, altitude distribution as well as physical and chemical properties. [Method] Based on determination of contents of soil heavy metals and soil physical and chemical properties from agricultural land in Central Yunnan Province, the relationship between soil heavy metals with soil type, altitude distribu- tion and soil physical and chemical properties were analyzed. [Result] The average contents of all heavy metals in farmland of Central Yunnan didn＇t extend their limits of Grade II in the National Soil Environmental Quality Standard （GB15618-1995）. and the heavy metals content in red soil was higher than that in other types. Soil Cd content changes slightly with the altitude, while contents of other heavy metals were greatly affected by altitude. There were extremely significant positive correlation between heavy metals and clay particle content, that is, soil with heavier texture has more heavy metals. There was positive correlation between pH and each heavy metal content; there were positive correlation between Mn with Pb, Cd, Hg and Hg; exchangeable Ca and Mg contents in soil show negative correlations with most heavy metals. [Conclusion] This study has provided scientific bases for the heavy metal management in Central Yunnan area.

关键词： Soil type Altitude distribution physical and chemical properties Heavy metals

Cameroon Green Energy Potentials: Field Survey of Production, Physico-chemical Analyses of Palm Kernel Oil for Industrial Applications

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Green and Sustainable Chemistry 2020年第3期10卷 57-71页

作者： Alang Michael Bong Ndikontar Maurice Kor Peter T. Ndifon Department of Inorganic Chemistry University of Yaoundé I Yaoundé Cameroon Department of chemical Engineering Catholic University of Cameroon (CATUC) Bamenda Cameroon

This paper reports a field survey undertaken to determine the availability of raw material for palm kernel oil commercial production for industrial applications. Both industrial and artisanal wastes from palm kernel oil production were also surveyed as raw material (palm kernel seeds) for green energy production. Results of the field study show that 22% of palm kernel seeds (which represents tons of waste) resulting from palm oil processing plants are dumped while at the artisanal level, 80% of palm kernel seed waste is dumped. Analysis of field study data shows that large amounts of waste palm kernel seeds are available to enable large scale production of palm kernel oil (PKO) for desirable industrial applications in green energy production. The paper also reports on the physical and chemical properties of Cameroon palm kernel oil (PKO). Palm kernel oil was extracted using mechanical press and solvent extraction. The palm kernel oil (PKO) from Cameroon was analyzed by standard physico-chemical methods. Results of the physical measurements show a specific gravity of PKO of 0.92 kg/L, viscosity of 26.03 cSt and at 5.93 cSt at 40°C and 100°C respectively, viscosity index of 185, pour point of 20°C, cloud point of 29

关键词： Field Survey Palm Kernel Oil Raw Material Energy Production physical and chemical properties Fatty Acids Iodine Value GC-MS