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美国山核桃在云南的引种研究进展及发展前景 被引量:25
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作者 习学良 XI +12 位作者 XUE LIANG 范志远 FAN zhi YUAN 董润泉 DONG RUN QUAN 张雨 ZHANG YU 《江西林业科技》 2001年第6期39-41,共3页
总结了云南53a来对美国山核桃引种、选种、生物学特性、生态适应性、苗木繁殖、丰产栽培、虫害防治的研究进展和示范推广情况。认为美国山核桃市场潜力大,在云南栽培效益高、适栽区域广、符合该省经济林树种结构调整需要,将来定会得到... 总结了云南53a来对美国山核桃引种、选种、生物学特性、生态适应性、苗木繁殖、丰产栽培、虫害防治的研究进展和示范推广情况。认为美国山核桃市场潜力大,在云南栽培效益高、适栽区域广、符合该省经济林树种结构调整需要,将来定会得到大力推广发展。 展开更多
关键词 美国山核桃 云南 引种 研究进展 发展前景
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山香圆育苗技术 被引量:2
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作者 徐清 XU +4 位作者 QING 钟志鸿 ZHONG zhi HONG 《江西林业科技》 2001年第6期12-13,共2页
山香圆是独特的中药树种。通过试验,总结了山香圆种子繁殖和扦插育苗技术及其田间管理措施。
关键词 中药 树种 扦插 山香圆 育苗技术
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Three new compounds from the leaves of Acanthopanax senticosus Harms 被引量:7
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作者 zhi 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第6期702-705,共4页
Three new compounds named (2E)prenyl benzoate-4-O-α-L-arabinopyranosyl (1→6) β-D-glucopyranoside (1), 7-methoxy-8-O-β-D-glucopyranosyl coumarin (2), and 3,4'-dihydroxy-3'-methoxy benzenepentanoic acid (3) ... Three new compounds named (2E)prenyl benzoate-4-O-α-L-arabinopyranosyl (1→6) β-D-glucopyranoside (1), 7-methoxy-8-O-β-D-glucopyranosyl coumarin (2), and 3,4'-dihydroxy-3'-methoxy benzenepentanoic acid (3) were isolated from the leaves of Acanthopanax senticosus Harms. The structures of new compounds were determined by means of 2D NMR experiments and chemical methods. 展开更多
关键词 COMPOUNDS new structures 2D NMR THREE MEANS ACID
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Modification of Montmorillonite through Intercalative Polymerization 被引量:3
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作者 Lin Jie +3 位作者 zhi Bing HAN 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第1期108-109,共2页
Montmorillonite (MMT) was modified through intercalative polymerization of phenol and formaldehyde catalyzed by oxalic acid. The modified montmorillonite was delaminated at large, as demonstrated by XRD and TEM studi... Montmorillonite (MMT) was modified through intercalative polymerization of phenol and formaldehyde catalyzed by oxalic acid. The modified montmorillonite was delaminated at large, as demonstrated by XRD and TEM studies. It can disperse easily in epoxy resin to form exfoliated nanocomposites. The nanoscale silicate platelets dispersed in water can be metallized by silver deposition. 展开更多
关键词 MONTMORILLONITE intercalative polymerization novolac resin nanocomposites.
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Synthetic security assessment based on variable consistency dominance-based rough set approach 被引量:3
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作者 赵亮 Xue zhi 《High Technology Letters》 EI CAS 2010年第4期413-421,共9页
Security assessment can help understand the security conditions of an information system and yieldresults highly conducive to the solution of security problems in it.Taking the computer networks in a certainuniversity... Security assessment can help understand the security conditions of an information system and yieldresults highly conducive to the solution of security problems in it.Taking the computer networks in a certainuniversity as samples,this paper,with the information system security assessment model as its foundation,proposes a multi-attribute group decision-making (MAGDM) security assessment method based ona variable consistency dominance-based rough set approach (VC-DRSA).This assessment method combinesVC-DRSA with the analytic hierarchy process (AHP),uncovers the inherent information hidden indata via the quality of sorting (QoS),and makes a synthetic security assessment of the information systemafter determining the security attribute weight.The sample findings show that this methoil can effectivelyremove the bottleneck of MAGDM,thus assuming practical significance in information system security assessment. 展开更多
关键词 粗糙集 一致性 基础 安全评价 优势 信息系统安全 安全评估方法 多属性群决策
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Direct Observation of Various Al Sites in SAPO-34 by ^(27)Al Multiquantum (MQ) Magic Angle Spinning (MAS) NMR 被引量:2
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作者 zhi Min +4 位作者 YAN Jian Qin ZHUANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第1期87-90,共4页
The elegant 2D multiquantum (MQ) MAS NMR has been applied to investigate the coordination of Al atoms in SAPO-34. The results show that the effects of the template and/or water on the coordination of Al atoms are sig... The elegant 2D multiquantum (MQ) MAS NMR has been applied to investigate the coordination of Al atoms in SAPO-34. The results show that the effects of the template and/or water on the coordination of Al atoms are significant, which lead to the formation of various Al species. Up to four kinds of Al species are distinctly resolved. 展开更多
关键词 SAPO-34 ^(27)Al MQ MAS NMR ^(27)Al MAS NMR structure.
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步进电机步距角的软件细分法 被引量:1
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作者 zhi Ai-Juan 智爱娟 《电机电器技术》 2005年第6期50-51,共2页
对步进电机的步距角进行细分是提高步进电机控制系统的速度和精度的最常用、最有效的方法.本文分析了步进电机步距角细分的原理,并重点介绍了一种用软件实现步进电机步距角细分的方法.
关键词 步进电机 软件 细分
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RELATIONSHIP BETWEEN THE EXPRESSIONS OF LMP1 AND ECADHERIN/β-CATENIN IN NASOPHARYNGEAL CARCINOMA
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作者 LIN Su-xia +18 位作者 林素暇 ZONG Yong-sheng 宗永生 CHU Bing 储兵 ZHONG Bi-ling 钟碧玲 LI zhi 李智 LIANG Ying-jie 梁英杰 LIN Han-liang 林汉良 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2002年第3期202-205,共4页
Objective: To compare the expression of Epstein-Barr virus encoded LMP1 and E-cadherin/β-catenin in primary and metastatic nasopharyngeal carcinoma (NPC) for the purpose of understanding their relationship. Methods: ... Objective: To compare the expression of Epstein-Barr virus encoded LMP1 and E-cadherin/β-catenin in primary and metastatic nasopharyngeal carcinoma (NPC) for the purpose of understanding their relationship. Methods: Twenty-two pairs of biopsies taken from the nasopharynx and cervical lymph node(s) of the same patient with nasopharyngeal carcinoma were collected. The expression of LMP1, E-cadherin and β-catenin was observed on immunostained slides using LSAB method. Results: The expression rate of LMP1 in the 22 metastatic tumors (86.36%, 19/22) was significantly higher than that in the 22 primary growths (68.18%, 15/22), P<0.05. The mean expression percentages of E-cadherin and β-catenin in metastatic tumors (50.11%±22.53% and 66.36±21.05%, respectively) were significantly lower than those in primary growths (71.52±24.34 % and 79.40%±15.05%, respectively), P<0.05. There was a positive correlation between the expressions of E-cadherin and β-catenin either in primary growths or metastatic tumors. Conclusion: The LMP1 is more likely to be expressed in metastatic neoplastic cells of NPC than in primary carcinoma cells, and on the contrary the expression of E-cadherin/β-catenin in metastatic cells was decreased. Accordingly, the LMP1 might have the ability to downregulate the expression of E-cadherin/β-catenin, resulting in enhancement of the invasive capacity of metastatic NPC cells. 展开更多
关键词 Nasopharyngeal tumor LMP1 E-CADHERIN Β-CATENIN INVASIVENESS
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Studies on Micellization of a Polystyrene-b-poly(acrylic acid) Copolymer in Aqueous Media by Pyrene Fluorescence
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作者 zhi Huai +4 位作者 Si Guo Chang WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第1期39-41,共3页
Pyrene probe and TEM have been employed to investigate the behavior of a polystyrene-b-poly(acrylic acid) (PS-b-PAA) copolymer in aqueous solution. A significant annealing temperature effect on the I1/I3 ratio of pyr... Pyrene probe and TEM have been employed to investigate the behavior of a polystyrene-b-poly(acrylic acid) (PS-b-PAA) copolymer in aqueous solution. A significant annealing temperature effect on the I1/I3 ratio of pyrene was observed and was interpreted in terms of the morphological change of micellar cores. Annealing at a temperature higher than the glass transition temperature (Tg) of PS leads to densification of the hydrophobic core. 展开更多
关键词 Polystyrene-b-poly(acrylic acid) micelle fluorescence pyrene.
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A Novel Alkaloid from Stemona parviflora
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作者 Chang Qing +3 位作者 zhi Sheng HE 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第2期173-175,共3页
关键词 Stemona parviflora perhydroazaazulene parvineostemonine.
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An Abnormal Reaction of N- (2,4-dinitrophenyl)-L-proline with Thionyl Chloride
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作者 zhi Bin +3 位作者 XU Zong Ru GUO 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第2期133-134,共2页
N- (2,4-Dinitrophenyl)-4-amino-n-butyl aldehyde 3 was obtained with high yield of 80% when N- (2,4-dinitrophenyl)-L-proline 1 reacted with SOCl2 at room temperature. However, the anticipated product N- (2,4-dinitroph... N- (2,4-Dinitrophenyl)-4-amino-n-butyl aldehyde 3 was obtained with high yield of 80% when N- (2,4-dinitrophenyl)-L-proline 1 reacted with SOCl2 at room temperature. However, the anticipated product N- (2,4-dinitrophenyl)-tetrahydropyrrolyl-2- (4-methylthiophenyl) ketone 2 did not be produced. The mechanism was discussed in this article. 展开更多
关键词 L-PROLINE 1-fluoro-2 4-dinitrobenzene(FDNB) N-(2 4-dinitrophenyl)-4-amino-n-butyl aldehyde.
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