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“大发”的来源及语法化过程
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作者 谢陈 朱怀 《忻州师范学院学报》 2021年第6期36-42,共7页
文章通过语料分析认为,现代汉语方言词"大发"的成词过程经历了三个阶段:(1)由"大+发+O"的跨层结构时期,(2)由跨层结构重新分析,逐渐凝固为动词的"大发",例如"诗兴大发";(3)由凝固结构的常用意... 文章通过语料分析认为,现代汉语方言词"大发"的成词过程经历了三个阶段:(1)由"大+发+O"的跨层结构时期,(2)由跨层结构重新分析,逐渐凝固为动词的"大发",例如"诗兴大发";(3)由凝固结构的常用意义固定而来,成为表"超过某种限度的性质或状态"的形容词,用作程度补语。且"大发"的使用具有一定的地域性,多见于北方作者作品之中。 展开更多
关键词 大发 来源 语法化 语用功能
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Nonlinear Absorption and Low-threshold Two-photon Pumped Amplified Stimulated Emission from FAPbBr_(3) Nanocrystals
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作者 WANG Yajuan TAY Yong Kang Eugene +3 位作者 WANG Fang YU Sheng SUM Tze Chien LIU Wei 《发光学报》 EI CAS CSCD 北大核心 2024年第8期1281-1291,共11页
Formamidinium lead bromide(FAPbBr_(3))nanocrystals(NCs)have been considered to be a good optoelectronic material due to their pure green emission,excellent stability and superior carrier transport characteristics.Howe... Formamidinium lead bromide(FAPbBr_(3))nanocrystals(NCs)have been considered to be a good optoelectronic material due to their pure green emission,excellent stability and superior carrier transport characteristics.However,two-photon pumped amplified spontaneous emission(ASE)and the corresponding nonlinear optical properties of FAPbBr_(3) NCs are scarcely revealed.Herein,we synthesized colloidal FAPbBr_(3) NCs with different sizes by changing the molar ratio of FABr/PbBr_(2) in the precursor solution,using ligand assisted precipitation(LARP)technology at room temperature.Photoluminescence(PL)and time resolved photoluminescence(TRPL)spectroscopy were measured to characterize their ASE properties.And their nonlinear optical properties were studied through the Zscan technique and the two-photon excited fluorescence method.The stimulated emission properties including oneand two-photon pumped ASE have been realized from FAPbBr_(3) NCs.With large two-photon absorption coefficient(0.27 cm/GW)and high non-linear absorption cross-section(7.52×10^(5) GM),ASE with threshold as low as 9.8μJ/cm^(2) and 487μJ/cm^(2) have been obtained from colloidal FAPbBr_(3) NCs using one-and two-photon excitations.These results indicate that as a new possible green-emitting frequency-upconversion material with low thresholds,FAPbBr_(3) NCs hold great potential in the development of high-performance two-photon pump lasers. 展开更多
关键词 perovskites formamidinium lead bromide nanocrystals NONLINEAR optical gain amplified spontaneous emission
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Changes of cell proliferation and differentiation in the developing brain of mouse 被引量:1
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作者 邱林 朱长连 +1 位作者 王小阳 徐发林 《Neuroscience Bulletin》 SCIE CAS CSCD 2007年第1期46-52,共7页
Objective To investigate the cell proliferation and differentiation in the developing brain of mouse. Methods C57/BL6 mice were divided into 3 groups at random. Bromodeoxyuridine (BrdU) was injected into the brains ... Objective To investigate the cell proliferation and differentiation in the developing brain of mouse. Methods C57/BL6 mice were divided into 3 groups at random. Bromodeoxyuridine (BrdU) was injected into the brains in different development periods once a day for 7 d. The brains were retrieved 4 weeks after the last BrdU injection. Immunohistochemical and immunofluorescent studies were carried out for detecting cell proliferation (BrdU) and cell differentiation (NeuN, APC, lbal, and S 100β), respectively. Results The number of BrdU labeled cells decreased significantly with the development of the brain. Cell proliferation was prominent in the cortex and striatum. A small portion of BrdU and NeuN double labeled cells could be detected in the cortex at the early stage of development, and in the striatum and CA of the hippocampus in all groups. The majority of BrdU labeled cells were neuroglia, and the number of neuroglia cells decreased dramatically with brain maturation. Neurogenesis is the major cytogenesis in the dentate gyrus. Conclusion These results demonstrated that cell proliferation, differentiation and survival were age and brain region related. 展开更多
关键词 brain development NEUROGENESIS GLIOGENESIS
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PHYLOGENETIC RELATIONSHIPS AMONG GIANT PANDA AND RELATED SPECIES BASED ON RESTRICTION SITE VARIATIONS IN rDNA SPACERS 被引量:5
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作者 兰宏 王文 《Zoological Research》 CAS CSCD 1998年第5期337-343,共7页
In this study, non radioactive Digoxigenin labeled ribosomal DNA(rDNA) probes were used for Southern blotting analysis to study the molecular phylogeny of the giant panda and related species. Restriction maps in the ... In this study, non radioactive Digoxigenin labeled ribosomal DNA(rDNA) probes were used for Southern blotting analysis to study the molecular phylogeny of the giant panda and related species. Restriction maps in the regions of rDNA spacers were compared between giant panda( Ailuropoda melanoleuca ), lesser panda( Ailurus fulgens ), Asiatic black bear( Selenarctos thibetanus ), sun bear( Helarctos malayanus ), raccoon( Procyon lotor ) and lynx( Felis lynx ). Phylogenetic trees for these species were constructed using maximum likelihood and parsimony method. The results show that in respect to rDNA RFLPs, the giant panda is more closely related to bear than to lesser panda; while the lesser panda is slightly related to the raccoon. 展开更多
关键词 Arctoidea The giant panda Ribosomal DNA restriction maps Phylogenetic relationships
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Fabrication and testing of phase change heat sink for high power LED 被引量:1
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作者 向建化 张春良 +2 位作者 江帆 刘晓初 汤勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第9期2066-2071,共6页
A novel phase change heat sink was fabricated for packaging cooling of high power light emitting diode (LED). 3D structures as enhanced boiling structure in the evaporation surface were composed of a spiral micro-gr... A novel phase change heat sink was fabricated for packaging cooling of high power light emitting diode (LED). 3D structures as enhanced boiling structure in the evaporation surface were composed of a spiral micro-groove along circumferential direction and radial micro-grooves which were processed by ploughing-extrusion (P-E) and stamping, respectively. Meanwhile, the cycle power of refrigerant was supplied by wick of sintered copper powder on internal surface of phase change heat sink. Operational characteristics were tested under different heat loads and refrigerants. The experimental results show that phase change heat sink is provided with a good heat transfer capability and the temperature of phase change heat sink reaches 86.8 ℃ under input power of 10 W LED at ambient temperature of 20 ℃. 展开更多
关键词 high power light emitting diode phase change heat sink enhanced boiling WICK heat transfer performance
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Changes in Levels of Endogenous Plant Hormones During Floret Development in Wheat Genotypes of Different Spike Sizes 被引量:11
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作者 曹卫星 王兆龙 戴廷波 《Acta Botanica Sinica》 CSCD 2000年第10期1026-1032,共7页
The levels of endogenous plant hormones regulate floret development and degeneration, and thus grain set in flower crops. This study was undertaken to characterize the changes of endogenous hormone levels during flor... The levels of endogenous plant hormones regulate floret development and degeneration, and thus grain set in flower crops. This study was undertaken to characterize the changes of endogenous hormone levels during floret development in three wheat ( Triticum aestivum L.) genotypes: “97J1' with the highest grain set and fertile florets per spike, “H8679' with the lowest grain set and fertile florets per spike, and a medium, “YM158'. The results showed that the peak level of ABA appeared between stamen and pistil differentiation and antherlobe formation of floret development, and the timing delayed with the size of spike (earliest in “H8679” and latest in “97J1”). From antherlobe formation to meiosis, the levels of ABA and GA 1+3 decreased sharply in the ears of “97J1”, while in the ears of “H8679” there was only a slight decrease in ABA, and even an increase in GA 1+3 . The ratio of isopentenyladenosine (iPA)/ABA and IAA/ABA in the ears of “97J1” increased sharply from antherlobe formation to meiosis, but changed only slightly in the ears of “H8679”. At antherlobe formation, IAA and GA 1+3 levels were higher in the ears of “97J1”, but lower in the ears of “H8679” than in the leaves. At meiosis, ABA, GA 1+3 and IAA levels in the “97J1” ears were much lower than in the leaves, but similar in “H8679”. These results indicated that the sharp decreases of ABA and GA 1+3 in ears from antherlobe formation to meiosis and the lowest maintenance at meiosis may be favorable for development of fertile florets and enhancement of grain set in wheat. 展开更多
关键词 WHEAT endogenous hormones floret development genotypic difference large ear
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Effects of Magnetized Water on Seed Germination of Welsh Onion (Allium fistulosum L.) 被引量:2
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作者 苗锦山 王树勇 游海英 《Agricultural Science & Technology》 CAS 2017年第5期777-779,784,共4页
With Welsh Onion seeds employed as materials, effects of magnetized water on seed Germination were studied. The results showed the treatment of magnetized water soaking for 4 h promoted water absorption rate and amyla... With Welsh Onion seeds employed as materials, effects of magnetized water on seed Germination were studied. The results showed the treatment of magnetized water soaking for 4 h promoted water absorption rate and amylase ac- tivities of seeds significantly, which accelerated the transformation process of en- dosperm starch to soluble sugar, resulting in emergence of 36 hours in advance under low temperature condition. Germination rate and germination potential of magnetized water soaking were higher than the contrast by 6.7% and 10.0%, which helped cultivate vigorous seedling. 展开更多
关键词 Magnetized water Welsh onion Seed germination Germination rate Germination potential
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Influence range of emergency under special events based on CTM 被引量:6
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作者 陈茜 李文权 《Journal of Southeast University(English Edition)》 EI CAS 2009年第2期257-261,共5页
To determine the dynamic influence range of emergencies under special events, the spacial and temporal characteristics of the traffic flow are studied by simulation based on the cell transmission model (CTM). Based ... To determine the dynamic influence range of emergencies under special events, the spacial and temporal characteristics of the traffic flow are studied by simulation based on the cell transmission model (CTM). Based on the traffic management measures used under special events, a semi-dynamic assignment algorithm is proposed, which is combined with an algorithm for logit multi-path traffic assignment and the CTM. In a simple calculation network, the spacial and temporal characteristics of traffic flows which vary with different traffic management schemes are studied, and a method to obtain the influence range of emergency is proposed by computing the jam time of the intersections. By contrasting the average delay of each vehicle, the dissipation effect is studied under two different traffic management schemes. The example shows that the spatial and temporal variety of the traffic flow can be easily simulated and the influence range of emergency can be confirmed by the method based on the CTM. The proposed method provides a new idea for decision-making on traffic management under emergency under special events. 展开更多
关键词 traffic management special event EMERGENCY influence range cell transmission model (CTM)
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Canadian English and its phonetic features 被引量:1
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作者 丁林棚 朱红梅 《Sino-US English Teaching》 2008年第1期50-55,共6页
British English and American English are regarded as the two major varieties of English in the world, and Canadian English is often treated as a variation of American English. The paper aims to identify the major phon... British English and American English are regarded as the two major varieties of English in the world, and Canadian English is often treated as a variation of American English. The paper aims to identify the major phonetic features of Canadian English by addressing its differences from British and American English based on a historical, demographical, and regional and dialectal analysis. Canadian English is a cultural phenomenon that has evolved on the basis of British English and under the heavy influence of American English. As a distinctive variety of English, Canadian English possesses its phonetic uniqueness. And in the context of globalization, Canadian English will remain subject to Americanization. 展开更多
关键词 Canadian English Canadian pronunciation English variety AMERICANIZATION phonetic differences
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Artificial incubation and growth observation for the nestlings of Great Bustard (Otis tarda) 被引量:2
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作者 田秀华 张佰莲 +1 位作者 刘群秀 何相宝 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期301-304,共4页
Growth indicators including weight, body length, wings length, tail length, tarsus, gape, the third toe and head width of 21 nestlings of Great Bustard (Otis tarda) were measured and investigated in Harbin Zoo, Harbin... Growth indicators including weight, body length, wings length, tail length, tarsus, gape, the third toe and head width of 21 nestlings of Great Bustard (Otis tarda) were measured and investigated in Harbin Zoo, Harbin, China during 1999-2002, and methods on successfully fostering nestlings of the bird were also summarized in this article. The results showed: the Great Bustard is a kind of premature bird and its birth weight was 86.31?.56g (N=21); environmental temperature for the neonatal nestlings should be controlled at 36C; the feeding principle having many meals but little food at each for the nestlings should be followed; since six weeks after birth, nestlings of both gender began to show significant difference in body weight, the weight of male was 1.8 times of that of the female after fourteenth week, and by weight and body figure sexual identity could be easily discerned when 3 or 4 months old; There is no significant difference in growth and development of all organs between male and female nestlings and organ growth curves were fit into Logistic equation. 展开更多
关键词 Artificial incubation Great bustard NESTLINGS GROWTH
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The influencing factors and Development Countermeasures of Large Farming Household in Jiangxi Province
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作者 戴天放 麻福芳 《Agricultural Science & Technology》 CAS 2015年第3期573-577,共5页
As an important part of the new agricultural business entities, large-scale grain-production households play a significantly positive role in improving the land resource utilization, improving agricultural productivit... As an important part of the new agricultural business entities, large-scale grain-production households play a significantly positive role in improving the land resource utilization, improving agricultural productivity, increasing agricultural output and farmers" income, and making a certain contribution to stabilize grain production. This paper analyzed the current situation of large-scale grain-production household in Jiangxi Province, as well as the problems in land transfer, farmland infrastructure, production and management, capital and other risks. At last, the paper proposed targeted countermeasures. 展开更多
关键词 Large farming household Development characteristics PROBLEMS COUNTERMEASURES
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Porcine Breeding Management in a Large-scale Piggery with Microbial Fermentation Bed 被引量:1
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作者 刘波 李兆龙 +6 位作者 唐建阳 黄勤楼 郑回勇 蓝江林 史怀 翁伯琦 余文权 《Agricultural Science & Technology》 CAS 2015年第1期160-166,171,共8页
[Objective] The behavior of eating, drinking, defecating and peeing of 1 500 pigs in a large-scale microbial fermentation bed-equipped piggery was observed. We hoped to find some simple indicators that could reflect t... [Objective] The behavior of eating, drinking, defecating and peeing of 1 500 pigs in a large-scale microbial fermentation bed-equipped piggery was observed. We hoped to find some simple indicators that could reflect the health status of swinery and to provide experience for the swinery performance management in large-scale microbial fermentation bed-equipped piggery. [Method] The body weight (BW), daily BW gain, feed intake and other indicators of different-day-old pigs were recorded in details. Based on the recorded data, the models between BW, BW gain, average daily feed intake and feed/gain ratio and growth days (d) were established. In addition, the incidences of pox-like macula (dermatitis), diarrhea (gastrointestinal disease), cough (respiratory disease), stiff pig (malnutrition), conjunctivitis (eye disease) and foot inflection (trauma) among fattening pigs were also investigated. [Result] The BW range, average BW, daily BW gain, breeding days, daily feed intake range, average daily feed intake, staged feed intake, accumulated feed intake, feed/gain ratio and accumulated feed/gain ratio of different-day-old pigs were studied, respectively. Four dynamic models were established for the growth of pigs: (1) the BW (y)-age (x) mod- el: y=0.758 9x-19.883 (3=0.993 7); (2) the BW gain (y)-age (x) model: y=1.039 5x05051 (F=0.885 4); (3) the average daily feed intake (y)-age (x) model: y=0.023 5x-0.334 3 (F=0.991 7); (4) the feed/gain ratio (y)-age (x) model: y=0.022x+0.427 8 (P=0.988 5). Based on these models, the corresponding theoretical growth value of pigs at different growth stage could be predicted. The main diseases occurred among the swinery in the large-scale microbial fermentation bed piggery included pox-like macula (dermatitis), diarrhea (gastrointestinal disease), cough (respiratory disease), stiff pig (mal- nutrition), conjunctivitis (eye disease) and foot inflection (trauma). The deadly infec- tious diseases had been not found among the pigs. [Conclusion] When the actual BW, BW gain, average daily feed intake and feed/gain ratio were all lower than the theoretical values predicted by the models, the management should be enhanced. The average daily feed intake of 60 to 65-day-old pigs was lower than the theoretic value, indicating that the pigs could not adapt nicely to the fermentation bed at the very early stage. When the pigs grew up to 70 to 75 d old, the average daily feed intake was higher than the theoretical value, indicating that the pigs had adapted to the fermentation bed. In particularly, average daily feed intake of 75-day-old pigs was higher than the theoretical value by 21%. It was suggested the fermentation bed was conducive to the growth of pigs. Considering the occurrence of diseases among pigs, the overall incidence was relatively low. The incidence of each disease was all lower than 10% with little difficulty in treating. If the management of mattress was strength- ened, such as paying attention to feeding and keeping water clean, many diseases could heal by themselves. 展开更多
关键词 Disease investigation Large-scale breeding Microbial fermentation bed Porcine growth model
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Histological Study on Soybean Somatic Embryogenesis 被引量:10
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作者 赵桂兰 杨向东 +1 位作者 郭东全 胡赞民 《Agricultural Science & Technology》 CAS 2008年第2期49-53,75,共6页
Soybean somatic cell could induce the development of embryoid which was similar to embryo morphologically and structurally. Somatic embryogenesis system of soybean was used to conduct genetic transformation of soybean... Soybean somatic cell could induce the development of embryoid which was similar to embryo morphologically and structurally. Somatic embryogenesis system of soybean was used to conduct genetic transformation of soybean because of its several advantages such as higher transformational efficiency, beetter synchronism and fewer plant chimeras among transgenic plants. After infected with agrobacterium tumefaciens,the initiation, differentiation and development of young cotyledon embryogenic cell of soybean which was cultured on selective culture medium with kanamycin were investigated through histological study. The result showed that somatic embryo was differentiated in non-bud differentiation way. The embryogenic cells were differentiated from epidermis of explant or cells in 1 layer or 2 layers, with the division of embryogenic cells and degradation and disorganization of surrounding cells, the embryogenic cells would form embryoid with analogous suspensor structure. Later, globular embryoid would extrude from epidermis then developed into heart-shape embryo. The experiment was expected to provide theoretical reference for the construction of high transformational system of using plant somatic embryogenesis induced by young cotyledon of soybean. 展开更多
关键词 SOYBEAN Somatic embryogenesis HISTOLOGY
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Characterization of a Cyclophilin cDNA from Soybean Cells
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作者 阚云超 刘士旺 +1 位作者 郭泽建 李德葆 《Acta Botanica Sinica》 CSCD 2002年第2期173-176,共4页
A cDNA clone encoded for cyclophilin (GmCyp1) was isolated by RT-PCR method from suspension-cultured soybean (Glycine max L.) cells. The deduced amino acid sequence was 91% identical to a kidney bean cyclophilin in t... A cDNA clone encoded for cyclophilin (GmCyp1) was isolated by RT-PCR method from suspension-cultured soybean (Glycine max L.) cells. The deduced amino acid sequence was 91% identical to a kidney bean cyclophilin in the open reading frame of the gene. Results from Southern blotting analysis suggests that the GmCyp1 belong to a small gene family in soybean cells. The time course of GmCyp1 mRNA accumulation upon treatment of elicitor from yeast extract did not show significant change in the time period examined. The data suggest that the GmCyp1 was not regulated much by biotic factors. A possible role of the cyclophilin in the plant-pathogen interaction was discussed. 展开更多
关键词 cyclophilin cDNA ELICITATION soybean cells
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Increased Endogenous Methyl Jasmonate Altered Leaf and Root Development in Transgenic Soybean Plants 被引量:7
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作者 薛仁镐 张标 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第4期339-346,共8页
Methyl jasmonate (MeJA) is a plant-signaling molecule that regulates plant morphogenesis and expression of plant defense genes. To determine the role of the endogenous MeJA levels in the development of plants, trans... Methyl jasmonate (MeJA) is a plant-signaling molecule that regulates plant morphogenesis and expression of plant defense genes. To determine the role of the endogenous MeJA levels in the development of plants, transgenic soybean [Glycine max (L.) Merrill] plants harboring NTR1 gene encoding for jasmonic acid carboxyl methyltransferase (JMT) were produced. The activation of NTR1 gene expression resulted in the production of MeJA. Overexpression of the NTR1 cDNA under the regulation of cauliflower mosaic virus (CaMV) 35S promoter in the transgenic soybean plants was confirmed using Northern blot analysis. The significant differences in leaf and root growth patterns were observed between the transgenic plants and the wild-type plants. The leaves of the transgenic plants were slightly elongated in length but dramatically narrowed in width compared with the nontrans-formed wild-type plants. In addition, elongation of primary root was inhibited in the overexpressed transgenic soybean plantlets, whereas the development of lateral root was stimulated relative to the nontransformed plants. The leaves of the transgenic plants showed 2-2.5-fold higher levels of MeJA than the control plants. These results indicated that the increased endogenous levels of MeJA is involved in regulation of morphogenesis in soybean plants. 展开更多
关键词 methyl jasmonate MORPHOGENESIS NTR1 OVEREXPRESSION SOYBEAN
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Phylogenetic Analysis of the Sequences of rDNA Internal Transcribed Spacer (ITS) of Phytophthora sojae 被引量:2
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作者 徐鹏飞 韩英鹏 +14 位作者 吴俊江 吕慧颖 邱丽娟 常汝镇 靳立梅 王金生 于安亮 陈晨 南海洋 许修宏 王萍 张大勇 张淑珍 李文滨 陈维元 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第2期180-188,共9页
The internal transcribed spacer (ITS) region (ITS1, ITS2 and 5.8S rDNA) of the nuclear ribosomal DNA (nrDNA) was amplified via the PCR method in seventeen different isolates of Phytophthora sojae using the commo... The internal transcribed spacer (ITS) region (ITS1, ITS2 and 5.8S rDNA) of the nuclear ribosomal DNA (nrDNA) was amplified via the PCR method in seventeen different isolates of Phytophthora sojae using the common primers of the ITS of fungi. Around 800 bp- 1,000 bp fragments were obtained based on the DL2000 marker and the sequences of the PCR products were tested. Taking isolate USA as outgroup, the phylogenetic tree was constructed by means of maximum parsimony analysis, and the genetic evolution among isolates was analyzed. The results showed that there is a great difference between the base constitution of ITS 1 and ITS2 among various isolates. The seventeen isolates are classified into three groups, and the isolates from the same region belong to the same group, which shows the variation in geography. 展开更多
关键词 SOYBEAN Phytophthora sojae RDNA PHYLOGENY
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A CMOS Power Amplifier with 100% and 18% Modulation Depth for Mobile RFID Readers
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作者 高同强 张春 +1 位作者 池保勇 王志华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第6期1044-1047,共4页
Aiming at the specific protocol of RFID technology,a 915MHz CMOS transmitter front-end for OOK modulation is implemented in a 0.18μm CMOS process. The transmitter incorporates a class-E power amplifier (PA), a modu... Aiming at the specific protocol of RFID technology,a 915MHz CMOS transmitter front-end for OOK modulation is implemented in a 0.18μm CMOS process. The transmitter incorporates a class-E power amplifier (PA), a modulator, and a control logic unit. The direct-conversion architecture minimizes the required on-and-off-chip components and provides a low-cost and efficient solution. A novel structure is proposed to provide the modulation depth of 100% and 18% ,respectively. The PA presents an output ldB power of 17.6dBm while maintaining a maximum PAE of 35.4%. 展开更多
关键词 CMOS power amplifier RFID TRANSMITTER modulation depth
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Structure Design of Large-scale Fattening Pig House with Fermentation Bed 被引量:2
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作者 刘波 蓝江林 +1 位作者 唐建阳 史怀 《Agricultural Science & Technology》 CAS 2014年第9期1521-1525,1529,共6页
The fattening pig house with fermentation bed had an area of 2 100 m2, and the area of fermentation bed was 1 900 m2 with a utilization rate of 91.4%, which was 45% higher than that of conventional pig house with surr... The fattening pig house with fermentation bed had an area of 2 100 m2, and the area of fermentation bed was 1 900 m2 with a utilization rate of 91.4%, which was 45% higher than that of conventional pig house with surrounding barrier. There was feeding trough around the house. The water troughs were set in the middle of the fermentation bed and of the feeding trough on the short sides of the house, separating feed and water. There were electric aluminum alloy shutters in both long sides of the house for ventilation, cooling and heat preservation. On both short sides, there were fans and wet curtains. The spray cooling devices were in- stalled outside the roof for cooling. The environmental control in the piggery, includ- ing light, temperature, water, humidity, carbon dioxide and ammonia, was realized to run by computer automatically. The coconut chaff and chaff configuration were used as mattress material, realizing the advantages of fermentation bed, such as no smell, zero emission, high-quality meat, saving labor, controlling disease, no drug residue, producing fertilizer, intelligent control, mechanized operation, etc. 展开更多
关键词 Fermentation bed Large-scale piggery Automatic control Non-pollution No smell
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Retrospect and Prospect of Excitation Systems of Large Size Turbogenerators
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作者 都兴有 《Electricity》 2002年第4期21-26,共6页
This paper briefs the developmental course, manufacturing and applications, as well as future prospect of excitation systems of large size turbogenerators in China, emphatically expounds the advantages of seif-excitat... This paper briefs the developmental course, manufacturing and applications, as well as future prospect of excitation systems of large size turbogenerators in China, emphatically expounds the advantages of seif-excitation systems with potential source reetifiers and matters needing to be noted during dissemination and application of them. 展开更多
关键词 thermal power plant large size turbogenerator excitation system self-shuntexcitation
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MECHANISM OF CHANGE IN THE CATION INDUCED EXCITA TION ENERGY DISTRIBUTION BETWEEN PSⅡ AND PSⅠ IN THE CHLOROPLAST MEMBRANE FROM ZOSTERA MARINA * 被引量:1
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作者 高振泮 娄清香 +4 位作者 马红 翟小京 马桂芝 毛大璋 李良璧 《Acta Botanica Sinica》 CSCD 1995年第11期833-841,共9页
The interrelations between thylakoid polypeptide components and Mg 2+ induced Chl a fluorescence and thylakoid surface charge changes were investigated in Zostera marina chloroplasts treated with Ca 2+ and... The interrelations between thylakoid polypeptide components and Mg 2+ induced Chl a fluorescence and thylakoid surface charge changes were investigated in Zostera marina chloroplasts treated with Ca 2+ and trypsin. It was observed that:1. The increase of Mg 2+ induced PSⅡ fluorescence intensity was closely related to the decrease of Mg 2+ induced surface charge density of the thylakoid membrane in the normal chloroplast; 2. Removal of the 32~34 kD polypeptides of the thylakoid surface by Ca 2+ extraction of the chloroplast did not affect the Mg 2+ induced phenomena; 3. If the Ca 2+ treated chloroplast was further digested by trypsin to remove the 26 kD polypeptide of the membrane surface, the Mg 2+ induced phenomena disappeared completely. These results clearly indicated that the 26 kD polypeptide of thylakoid surface is the specific acting site of the cation that induced these two correlated phenomena in the chloroplast from Zostera marina. The mechanism on the regulating effect of the cation on excitation energy distribution between PSⅡ and PSⅠ was discussed. 展开更多
关键词 CHLOROPLAST PHOTOSYSTEM Excitation energy distribution
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