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黑胸散白蚁的研究 被引量:13
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作者 刘源智 《中华卫生杀虫药械》 CAS 2003年第4期8-12,共5页
黑胸散白蚁(Reticulitermes chinensis)是Shyder1923年定名发表的一个蚁种,模式产地在四川宜宾.黑胸散白蚁在我国广布于北京以南各省,以木材及其纤维制品为食,危害房屋建筑、园林树木等许多方面,危害的严重性与台湾乳白蚁不相上下,是我... 黑胸散白蚁(Reticulitermes chinensis)是Shyder1923年定名发表的一个蚁种,模式产地在四川宜宾.黑胸散白蚁在我国广布于北京以南各省,以木材及其纤维制品为食,危害房屋建筑、园林树木等许多方面,危害的严重性与台湾乳白蚁不相上下,是我国几大成灾蚁种之一. 展开更多
关键词 黑胸散白蚁 分飞 生活周期 补充生殖蚁 品质分化
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Analysis and Optimum Design of Differential Inductors Using Distributed Capacitance Model
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作者 菅洪彦 唐长文 +1 位作者 何捷 闵昊 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第6期1077-1082,共6页
A distributed capacitance model for monolithic inductors is developed to predict the equivalently parasitical capacitances of the inductor.The ratio of the self-resonant frequency (f SR) of the differential-driven sym... A distributed capacitance model for monolithic inductors is developed to predict the equivalently parasitical capacitances of the inductor.The ratio of the self-resonant frequency (f SR) of the differential-driven symmetric inductor to the f SR of the single-ended driven inductor is firstly predicted and explained.Compared with a single-ended configuration,experimental data demonstrate that the differential inductor offers a 127% greater maximum quality factor and a broader range of operating frequencies.Two differential inductors with low parasitical capacitance are developed and validated. 展开更多
关键词 distributed capacitance model self-resonant frequency ratio quality factor differential inductor optimum design
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Quality Evaluation and Comprehensive Analysis of Flue-cured Tobacco Leaf in Fuzhou 被引量:2
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作者 冯小虎 李琰琰 《Agricultural Science & Technology》 CAS 2016年第1期168-174,共7页
The appearance quality, physical properties, chemical components and sensory quality of 69 flue-cured tobacco leaf samples from 6 counties of Fuzhou City in 2013 were analyzed and evaluated, and were compared with tho... The appearance quality, physical properties, chemical components and sensory quality of 69 flue-cured tobacco leaf samples from 6 counties of Fuzhou City in 2013 were analyzed and evaluated, and were compared with those in southeast area of China. The results showed that the flue-cured tobacco leaves in Fuzhou in 2013 had better hygroscopicity, toughness and filling ability, as well as suitable dragging force. However, some of the tobacco leaves were slightly thin, and had relatively high stem ratio. The tobacco leaves in Fuzhou had higher potassium content, lower starch content, and higher potassium to chlorine ratio. The middle tobacco leaves had better coordination of chemical components and general sensory quality(medium to medium-super level). Most upper and middle flue-cured tobacco leaf samples had medium-super aroma quality, relatively sufficient aroma quantity,and relatively concentrated smoke; while the lower flue-cured tobacco leaves had little aroma quantity and insufficient smoke. The appearance quality score of lower tobacco leaf samples in Fuzhou in 2013 was slightly lower than that in southeastand whole China. The scores of maturity and leaf structure of middle tobacco leaves in Fuzhou were equivalent to those in southeast China and the national averages.The upper leaves in Fuzhou obtained an equivalent score in oil content and slightly lower scores in other indexes as compared with those in southeast China.The middle-lower tobacco leaves in Fuzhou had better hygroscopicity and toughness compared with those in southeastand whole China. The total alkaloid content per plant andreducing sugar content and potassium content in the middle and lower parts were higher than those in southeast and whole China. However, the scores of coordination of chemical components of lower and upper tobacco leaves in Fuzhou were slightly lower than those in southeast and whole China. The sensory quality of the 3 parts of tobacco leaves in Fuzhou were similar to that in southeast and whole China, but the score of consistency of upper tobacco leaves in Fuzhou was slightly higher. 展开更多
关键词 Fuzhou Tobacco quality Chemical component Analysis and evaluation
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Effects of 60Co-γ Ray Radicidation on Instant Tea 被引量:2
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作者 Wang Qian,Peng Ling,Li Wenge,and Deng Gangqiao Hunan Institute of Atomic Energy Application in Agriculture,Changsha,Hunan 410125 《Hunan Agricultural Science & Technology Newsletter》 2001年第1期21-23,共3页
Effects of 60Co-γ ray radicidation on instant tea were studied through contaminant microbe assay,absorbed dose measurement and analysis of principal components of instant tea.The minimum effective dose of 4.0kGy and ... Effects of 60Co-γ ray radicidation on instant tea were studied through contaminant microbe assay,absorbed dose measurement and analysis of principal components of instant tea.The minimum effective dose of 4.0kGy and maximum tolerance dose of 8.0KGy were proposed. 展开更多
关键词 instant tea radicidation D10 value
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Advances of the Vertical Directional Solidification Technique for the Growth of High Quality GaSb Bulk Crystals 被引量:2
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作者 Dattatray Bhairu Gadkari 《Journal of Chemistry and Chemical Engineering》 2012年第1期65-73,共9页
Advantages of the detached phenomena have influenced researchers to modify the conventional methods to promote it on the earth. Since 1994, the vertical directional solidification (VDS) technique has been employed f... Advantages of the detached phenomena have influenced researchers to modify the conventional methods to promote it on the earth. Since 1994, the vertical directional solidification (VDS) technique has been employed for the growth of bulk crystals, without the seed, without contact to the ampoule wall, without coating and without external pressure. An automated furnace was designed and fabricated for the controlled temperature gradients, growth conditions and parameters. The typical ingots growths of GaSb have shown the gap of 20 μm-145 μm and mobility μn = 1125 cm^2/V.sec at 300 K. Mobility is highest and five times larger than the attached growths. Dislocation density is the order of 104/cm2 in the conical region, decreases in the direction of growth, and in many crystals reached less than 103/cm2. The spontaneous gap formation due to the meniscus depends on the pressure differences and thermal state. GaSb grown ingots have shown progress in the properties of crystal grown ever, and attributed to reduce thermal stress without contact to the ampoule wall. 展开更多
关键词 SOLIDIFICATION growth from melt ANTIMONIDES semiconduction Ⅲ-Ⅴ crystal structure detached growth.
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Research and Application of Computer Management of the Test Chemical Products Quality Analysis 被引量:4
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作者 Hairui Zhang Guofu Zhang Helin Ye 《Journal of Chemistry and Chemical Engineering》 2015年第2期149-151,共3页
According to the regulations of the People's Republic of China national standard as the basis, on the part of chemical industry product quality inspection and analysis of the implementation of computer management has... According to the regulations of the People's Republic of China national standard as the basis, on the part of chemical industry product quality inspection and analysis of the implementation of computer management has developed a set of software applications, the software in chemical products quality inspection and analysis of the means of management is an innovation. The software functions, can automatically process data, judge the product grade, quality analysis, objective and fair, convenient, fast, accurate, stable, practical, and easy to popularize. 展开更多
关键词 Chemical products quality ANALYSIS automatic evaluation software development application.
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Effect of Long-Term in Vitro Sub-culturing on Quality Degeneration of Sweet Potato Varieties: Morpho- Anatomic Assessment and Simple Sequence Repeats Analysis
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作者 Mihiretu Cherinet Hundayehu Elsa Du Toit +3 位作者 Sunette Laurie Martin Steyn Ria Greyling Nokuthula Myeza 《Journal of Agricultural Science and Technology(A)》 2014年第10期811-821,共11页
The aim of this study was to assess the effect of long-term in vitro sub-culturing on the varietal degeneration of three sweet potato varieties, namely, Monate, Mokone and Ndou which were sub-cultured for 32, 23 and 1... The aim of this study was to assess the effect of long-term in vitro sub-culturing on the varietal degeneration of three sweet potato varieties, namely, Monate, Mokone and Ndou which were sub-cultured for 32, 23 and 12 generations, respectively. Each generation was cultured in a media which is made from 4.43 g/L Murashige and Skoog (MS), 30 g/L sucrose and 2 g/L gelrite, respectively, and grown under 16 h light and 8 h dark photoperiod for 30 d. For each generation, 45 plantlets were acclimatized for two months in a glasshouse. Data on in vitro growth performance and 11 morphological characteristics during acclimatization were recorded. Early root and shoot formation was observed after the 27th and 21st sub-cultured generations of Monate and Mokone, respectively. During acclimatization, plantlets from the same variety showed differences in morphological traits such as leaf colour, abaxial leaf pigmentation, vine pigmentation, petiole pigmentation, leaf wrinkling and flowering. However, the rate of these morphological differences is random and irrespective to increase in sub-culturing. Therefore, to understand the genetic base of these morphological variability, two plantlets from each variety were subjected to genetic analysis by using five simple sequence repeat (SSR) primers (IB-242, IB-318, IB-255F, 1B-248 and IB-255). Although SSR loci IB-255F and IB-318 could distinguish between the three varieties, there were no allelic polymorphisms detected in plantlets from the same varieties. Therefore, long-term sub-culturing do not leads to quality degeneration in the three sweet potato varieties. 展开更多
关键词 MICRO-PROPAGATION ORGANOGENESIS SUB-CULTURE true-to-type morphology polymorphism.
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Enhanced exergy cost optimization of operating conditions in FCCU main fractionator
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作者 Chonglin Zhong Yi Zheng +1 位作者 Shenghu Xu Shaoyuan Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第8期1750-1757,共8页
Exergy indicates the maximal energy that can do work effectively. Different from optimization of product quality or calculation of generic energy conservation in most previous studies, the application of exergy analys... Exergy indicates the maximal energy that can do work effectively. Different from optimization of product quality or calculation of generic energy conservation in most previous studies, the application of exergy analysis and exergy cost optimization in petrochemical industry is of great economic and environmental significance. Based on the main fractionator in Jiujiang Petrochemical Complex No. 2 FCCU, an enhanced exergy cost optimization under different operating conditions by adjusting set points of temperature and valves opening degree for flow control is studied in this paper in order to reduce exergy cost and improve the quality of energy. A steadystate optimization algorithm to enhance exergy availability and an objective function comprehensively considering exergy loss are proposed. On the basis of ensuring the quality of petroleum products, the economic benefits can be improved by optimizing the controllable variables due to the fact that exergy cost is decreased. 展开更多
关键词 EXERGY Optimization of operating conditions FRACTIONATOR FCCU Exergy Cost
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Improvement of saponification extraction method for fatty acids separation from geological samples
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作者 Jiang Chang Yanqing Xia +2 位作者 Suping Ma Xuan Fang Minzhuo Sun 《Acta Geochimica》 EI CAS CSCD 2016年第2期148-155,共8页
The conventional saponification method could result in lower recoveries and artificial changes of longchain fatty acids. The main reason is the error judgment of the intermediate layer suspended between the aqueous an... The conventional saponification method could result in lower recoveries and artificial changes of longchain fatty acids. The main reason is the error judgment of the intermediate layer suspended between the aqueous and organic layer during the liquid–liquid extraction process.This study shows that the intermediate layer consists of lots of medium- to long-chain carboxylic salts for their special physical and chemical properties. An improved saponification extraction method is also developed and the results show that the carboxylic salts distributed in the intermediate layer could be obtained completely, which greatly enhances the authenticity and accuracy of fatty acid analysis. Additionally, the possible reasons of formation of the intermediate layer are also discussed. 展开更多
关键词 Fatty acid SEPARATION Saponificationextraction Carboxylic salt Geological sample
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Superparamagnetic Supported Catalyst H_3PW_(12)O_40/γ-Fe_2O_3 for Alkylation of Thiophene with Olefine 被引量:1
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作者 许翠霞 杨克迪 +5 位作者 刘自力 秦祖赠 何维 代倩雯 张健杰 张帆 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第3期305-311,共7页
The alkylation of sulfur compounds with olefine is considered to be an attractive way to attain high level of sulfur removal by raising the boiling point of sulfur-containing compounds to ease their separation from li... The alkylation of sulfur compounds with olefine is considered to be an attractive way to attain high level of sulfur removal by raising the boiling point of sulfur-containing compounds to ease their separation from lighl fractions by distillation. A series of superparamagnetic supported catalysts, used for alkylation of thiophene with 1-octene, were prepared by loading H3PW12040 (HPW) onto commercially available nanoparticles γ-Fe2O3 through incipient wet impregnation method. The catalysts were characterized by X-ray diffraction (XRD), Fourier transform infra-red (FT-IR), thermo gravimetric analysis (TG), N2-adsorption and vibrating sample magnetometer (VSM). The physicochemical characterization reveals that 7-Fe203 could be accommodated to immobilize and disperse HPW. Moreover, possessing high magnetization of 26.1 A.mZ.kg-1 and with mesoporous structure with specific surface area of 35.9 m2·g^-1, the 40% (by mass) HPW loading catalyst is considered the proper catalyst for olefinic alkylation of thiophenic sulfur (OATS) and can be separated in an external magnetic field. The catalytic activity was investigated in the alkylation reaction of thiophene with 1-octene, and the conversion of thiophene is up to 46% at 160 ℃ in 3 h. The 40% (by mass) H3PW12O40/γ-Fe2O3 catalyst can be reused 6 times without too much loss of activit and keeps its property of superparamagnetism. 展开更多
关键词 ALKYLATION HETEROPOLYACID THIOPHENE superparamagetism
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Investigation of Geographical Origin and Production Method of L(+)-Tartaric Acid by Isotopic Analyses with Chemometrics
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作者 Glaucia Danielle Leirose Marie-Florence Grenier-Loustalot Arno Heeren de Oliveira 《Journal of Chemistry and Chemical Engineering》 2017年第2期45-50,共6页
The determination of the geographical origin as well as the adulteration of natural products is a technical problem due to similar chemical composition between an adulterant and the original. It is assumed that tartar... The determination of the geographical origin as well as the adulteration of natural products is a technical problem due to similar chemical composition between an adulterant and the original. It is assumed that tartaric acid comes from natural sources, however there is no specific regulation for this claim. This paper describes the use of isotope mass spectrometry associated with chemometrics to classify different samples of tartaric acid. The results showed that the variables δ^13C, δ^18O and δ^2H allowed the discrimination of tartaric acid samples by geographical origin and production method. By using a combination of chemometfic analysis it was possible to confirm a notoriousseparation of the samples. Thus, this is a promising method to be applied in the quality control and authenticity of tartaric acid. 展开更多
关键词 Tartaric acid multi-isotope analysis food authenticity geographical origin isotopic mass spectrometry.
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Additive effects due to biochar and endophyte application enable soybean to enhance nutrient uptake and modulate nutritional parameters
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作者 Muhammad WAQAS Yoon-Ha KIM +6 位作者 Abdul Latif KHAN Raheem SHAHZAD Sajjad ASAF Muhammad HAMAYUN Sang-Mo KANG Muhammad Aaqil KHAN In-Jung LEE 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2017年第2期109-124,共16页
We studied the effects of hardwood-derived biochar(BC) and the phytohormone-producing endophyte Galactomyces geotrichum WLL1 in soybean(Glycine max(L.) Merr.) with respect to basic, macro- and micronutrient upta... We studied the effects of hardwood-derived biochar(BC) and the phytohormone-producing endophyte Galactomyces geotrichum WLL1 in soybean(Glycine max(L.) Merr.) with respect to basic, macro- and micronutrient uptakes and assimilations, and their subsequent effects on the regulation of functional amino acids, isoflavones, fatty acid composition, total sugar contents, total phenolic contents, and 1,1-diphenyl-2-picrylhydrazyl(DPPH)-scavenging activity. The assimilation of basic nutrients such as nitrogen was up-regulated, leaving carbon, oxygen, and hydrogen unaffected in BC+G. geotrichum-treated soybean plants. In comparison, the uptakes of macro- and micronutrients fluctuated in the individual or co-application of BC and G. geotrichum in soybean plant organs and rhizospheric substrate. Moreover, the same attribute was recorded for the regulation of functional amino acids, isoflavones, fatty acid composition, total sugar contents, total phenolic contents, and DPPH-scavenging activity. Collectively, these results showed that BC+G. geotrichum-treated soybean yielded better results than did the plants treated with individual applications. It was concluded that BC is an additional nutriment source and that the G. geotrichum acts as a plant biostimulating source and the effects of both are additive towards plant growth promotion. Strategies involving the incorporation of BC and endophytic symbiosis may help achieve eco-friendly agricultural production, thus reducing the excessive use of chemical agents. 展开更多
关键词 Phytohormone-producing endophytic fungi Nutrients uptake ASSIMILATION Nutritional quality SOYBEAN
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