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Study on Sesame Export for Sudan Based on Gravity Model

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World Journal of Engineering and Technology 2017年第2期5卷 31-39页

作者： Mansour Yousif Ahmed Adam Shiwei Xu Wen Yu Shengwei Wang siek darith Agricultural Information Institute Chinese Academy of Agricultural Sciences Beijing China Key Laboratory of Digital Agricultural Early-Warning Technology Ministry of Agriculture Beijing China

This study aimed to investigate the effect of social and economic differences between importer and exporter countries on trade flows of Sesame seed product. The analysis was carried out by estimating the gravity model. The sample covered a total of 14 countries for the period from 1997 to 2009. The results showed that the social and economic differences between countries have a significant and positive or negative effect on Sesame seeds trade. Furthermore, we found that the same language, distance and sesame production in export country have positive effect for the sesame export from Sudan.

关键词： Sesame Trade Gravity Model Sudan Partner Countries Policy

Potentials and Constraints of Small-Scale Livestock Productions in Cambodia

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World Journal of Engineering and Technology 2017年第2期5卷 15-22页

作者： siek darith Shiwei Xu Wen Yu Ahmed Abdul-Gafar Sa Kennvidy Ou Ratanak Eric Mukeba Mbala Agricultural Information Institute Chinese Academy of Agricultural Sciences Beijing China Regional Polytechnic Institute TechoSen Battambang Ministry of Labor and Vocational Training Battambang Cambodia Graduate School of Agricultural Science Royal University of Agriculture Phnom Penh Cambodia

Livestock husbandry plays a very important role in rural areas of Cambodia. Farmers mostly have complained about the declining revenue from livestock production which supports their livelihood. Therefore, the study aimed at investigating the potentials and constraints of smallholder livestock productions in Battambang province. Primary and secondary data were collected to meet the objectives. Data were collected interviewing 204 households. Some of the advantages of the Cambodia livestock subsector are the increasing market demand: increasing domestic market for livestock and increasing demand from neighboring countries (especially cattle);the rich source of manure and other agricultural input such as transportation means, ploughing etc. More so, there is high expectation of the farmers experiencing increase in production since more supports are provided by both governmental and non-governmental organizations. On the other hand, the subsector witnesses some constraints including the low level of education of the livestock farmers, erratic market prices as a result of too many middlemen, local breed with low productivity and traditional management system still dominates the sub- sector. Scarcity of abled labor and seasonal cost is also one of the factors impeding the subsector to reaching it potential. This study suggests that to reach full potential in the livestock sector of Battambang of Cambodia, the government needs to address the infrastructural problems and private sector needs to be encouraged to invest in the sector in livestock input industries.

关键词： Potential Constraints Livestock Production Battambang Cambodia

Study on Food Import in D. R. Congo

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World Journal of Engineering and Technology 2017年第2期5卷 23-30页

作者： Mukeba Mbala Eric Shiwei Xu Wen Yu Shengwei Wang Abdul-Gafar Ahmed siek darith Mujinga Bukasa Eliane Agricultural Information Institute Chinese Academy of Agricultural Sciences Beijing China Key Laboratory of Digital Agricultural Early-Warning Technology Ministry of Agriculture Beijing China

Democratic Republic of Congo is a developing country located in Central Africa with a population of over 75 million. Generally, it relies on import in international market for food as it has constantly been experiencing domestic crisis which hinders production. Given the importance of shores price policy and income policy, the government pays meticulous attention to these factors to meet the present and future food security. In order to understand the import behavior related to GDP and international trade prices, the study employs Almost Idea Demand System (AIDS) model using FAO data. The result explains that price effect is more useful to the food security of the country than the income effect, thus this study suggest the government should give priority to policy on price.

关键词： Agricultural Import Almost Ideal Demand System (AIDS) D. R. Congo Policy

Mixed-Charge,pH-Responsive Nanoparticles for Selective Interactions with Cells,Organelles,and Bacteria

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Accounts of Materials Research 2020年第3期1卷 188-200页

作者： Marta siek Kristiana Kandere-Grzybowska Bartosz A.Grzybowski Center for Soft and Living Matter Institute for Basic Science(IBS)Ulsan 44919Republic of Korea Department of Biomedical Engineering Ulsan National Institute of Science and Technology(UNIST)Ulsan 44919Republic of Korea

CONSPECTUS:Charged interfaces are ubiquitous in biology,from proteins,to membranes enclosing cells and organelles,to bacterial cell *** nanomaterials to interact with these biological entities effectively and selectively,their electrostatic properties must be *** date,charged nanomaterials have had their surfaces decorated with a single type of charged ligands(positive,negative,or zwitterionic),sometimes“diluted”with additional uncharged/hydrophobic *** such materials have shown some promise,they can be nonselectively cytotoxic or membrane-permeable,and can nonspecifically adsorb serum proteins or display limited cellular *** this Account,we review a decade of our work on pH-responsive nanoparticles(NPs)covered with mixtures of oppositely charged *** so-called mixed-charge nanoparticles(MCNPs)comprise d∼4−12 nm Au cores protected with mixed monolayers comprising positively charged N,N,N-trimethyl(11-mercaptoundecyl)ammonium chloride(TMA,[+])and negatively charged mercaptoundecanoic acid(MUA,[−])ligands at varying and precisely adjustable *** MCNPs are pH-responsive because MUA ligands can be protonated at a lower pH and,instead of interacting electrostatically,can engage in hydrogen ***,by adjusting the proportion of TMA and MUA functional groups on the particles’surfaces,(χTMA:χMUA)NP,and/or particle sizes,the relative balance between electrostatic,hydrogen bonding,and van der Waals forces can be tuned,translating into pH-dependent stability versus aggregation of the *** this way,MCNPs resist aggregation at the pH of healthy tissues and blood,but they precipitate or even crystallize at a narrow range of acidic pHs,characteristic of extracellular space surrounding tumors as well as intracellular endolysosomal *** harnessed this propensity of MCNPs to aggregate at the desired pH to target low-pH lysosomes in cancer *** we showed,MCNPs with compositions around(χTMA:χMUA)NP=8

关键词： impaired walls aggregation

Self-assembly of nitrogen-doped TiO_(2) with exposed {001} facets on a graphene scaffold as photo-active hybrid nanostructures for reduction of carbon dioxide to methane

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Nano Research 2014年第10期7卷 1528-1547页

作者： Wee-Jun Ong Lling-Lling Tan Siang-Piao Chai siek-Ting Yong Abdul Rahman Mohamed Low Carbon Economy(LCE)Group Chemical Engineering DisciplineSchool of EngineeringMonash UniversityJalan Lagoon Selatan46150 Bandar SunwaySelangorMalaysia Low Carbon Economy(LCE)Group School of Chemical EngineeringUniversiti Sains MalaysiaEngineering CampusSeri Ampangan14300 Nibong TebalPulau PinangMalaysia

Tailored synthesis of well-defined anatase TiO_(2)-based crystals with exposed{001}facets has stimulated incessant research interest worldwide due to their scientific and technological ***,anatase nitrogen-doped TiO_(2)(N-TiO_(2))nanoparticles with exposed{001}facets deposited on the graphene(GR)sheets(N-TiO_(2)-001/GR)were synthesized for the first time via a one-step solvothermal synthetic route using NH4F as the morphology-controlling *** experimental results exemplified that GR was uniformly covered with anatase N-TiO_(2) nanoparticles(10-17 nm),exposing the{001}*** percentage of exposed{001}facets in the N-TiO_(2)-001/GR nanocomposites was calculated to be ca.35%.Also,a red shift in the absorption edge and a strong absorption in the visible light range were observed due to the formation of Ti-O-C bonds,resulting in the successful narrowing of the band gap from 3.23 to 2.9 *** photocatalytic activities of the as-prepared photocatalysts were evaluated for CO_(2) reduction to produce CH,in the presence of water vapor under ambient temperature and atmospheric pressure using a low-power 15 W energy-saving daylight lamp as the visible light source--in contrast to the most commonly employed high-power xenon lamps--which rendered the process economically and practically *** all the studied photocatalysts,the N-TiO_(2)-001/GR nanocomposites exhibited the greatest CH4 yield of 3.70 p-mol'gcatalyst 1,approxi-mately 11-fold higher activity than the TiO_(2)-*** enhancement of photocatalyfic performance was ascribed to the effective charge anti-recombination of graphene,high absorption of visible light region relative to the{101}*** high catalytic activity of{001}facets.

关键词： photocatalysis nitrogen-doped TiO_(2) {001}facet acid treated solvent exfoliated graphene carbon dioxide reduction visible light

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使食品检测更高效

实验与分析 2012年第5期 42-43页

作者： Jeffery S. Partric K. siek Juergen Wendt

快速、安全地检测食品中有害物质残留物高效的分析手段是保证食品安全的有效手段．在分析食品中有害物质污染时，HPLC与高分辨率的TOF-MS的结合能发挥重要的作用。

关键词：食品检测有害物质污染 TOF-MS 食品安全高分辨率 HPLC 残留物结合能