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Two New Coumarins from the Roots of Aegle marmelos Xiu Wei Yang 1, Masao Hattori 2 and Tsuneo Namba 2
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作者 杨秀伟 服部征雄 难波恒雄 《Journal of Chinese Pharmaceutical Sciences》 CAS 1996年第2期68-73,共6页
Two new coumarins, named marminal (13) and 7' O methylmarmin (15), along with nineteen known compounds: ( sitosteryl pentadecanoate (1), 4 methoxy 1 methyl 2 quinolone (2), aurapten (3), 4 sitosten 3 on... Two new coumarins, named marminal (13) and 7' O methylmarmin (15), along with nineteen known compounds: ( sitosteryl pentadecanoate (1), 4 methoxy 1 methyl 2 quinolone (2), aurapten (3), 4 sitosten 3 one (4), lupeol (5), imperatorin (6), xanthotoxin (7), dictamnine (8), (+) epoxyaurapten (9), ( sitosterol (10), ( fagarine (11), skimmianine (12), scoparone (14), umbelliferone (16), scopoletin (17), decursinol (18), marmesin (19), marmin (20), and integriquinolone (21) were isolated from the methanolic extract of the roots of Aegle marmelos Corr. (family Rutaceae). 展开更多
关键词 Aegle marmelos COUMARINS Marminal 7' O methylmarmin
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Cloning of Banana Bunchy Top Virus Chinese Zhangzhou Isolate DNA 4 and the Promoter Activity of Its Non_coding Region
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作者 孙德俊 魏红艳 +1 位作者 蔡文启 田颖川 《Acta Botanica Sinica》 CSCD 2002年第8期941-945,共5页
Banana bunchy top virus Chinese Zhangzhou isolate (BBTV-ZZ) DNA 4 was amplified by PCR and cloned. Sequence analysis showed that BBTV-ZZ DNA 4 is 1 039 nucleotides (nts) in length and this virus could be one member of... Banana bunchy top virus Chinese Zhangzhou isolate (BBTV-ZZ) DNA 4 was amplified by PCR and cloned. Sequence analysis showed that BBTV-ZZ DNA 4 is 1 039 nucleotides (nts) in length and this virus could be one member of BBTV Asian group. Transcriptional initiation site A, which is at the 269 nucleotide, was preliminarily determined by using 5' RACE method. BBTV-ZZ DNA 4 non-coding region was sub-cloned by PCR and inserted into upstream of gfp : : gus plant expression vector pCAMBIA 1304 to construct recombinant plasmid pTA2. Agrobacterium tumefaciens harboring pTA2 was injected into leaves of the tobacco (Nicotiana tabacum L. cv. Xanthi NC) via Agrobacterium-infiltration procedure. Transient expressions of GUS and GFP were determined in injected leaves 3 - 5 d later. GUS activities of pTA2, pCAMBIA 1304 injected and non-injected tobacco leaves respectively were 1.007 0 pmol MU(.)mug(-1.)min(-1), 2.069 0 pmol MU(.)mug(-1.)min(-1) and 0.021 4 pmol MU(.)mug(-1.)min(-1). Indirect ELISA for GFP in 1 mg total protein from pTA2, pCAMBIA 1304 injected and non-injected leaves showed an A(490 nm) value of 89.577, 100.440 and 3.287, respectively. These results showed that the non-coding region of BBTV-ZZ DNA 4 has a promoter activity not only in the virus replication in monocot, but also in driving the expression of a foreign gene in dicot plants. 展开更多
关键词 banana bunchy top virus Chinese Zhangzhou isolate DNA 4 5 ' RACE PROMOTER GFP GUS
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Stability for the Manifold of Equilibrium State of the Autonomous Birkhoff System 被引量:3
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作者 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1997年第2期106-109,共4页
Studies the stability for them manifold of equilibrium state of the autonomous Birkhoffsystem. Uses the Liapunov's direct method and the first approximation method to obtain thestability criterion for the manifold... Studies the stability for them manifold of equilibrium state of the autonomous Birkhoffsystem. Uses the Liapunov's direct method and the first approximation method to obtain thestability criterion for the manifold of equilibrium state of the system. Gives an example toillustrate the application of the result. 展开更多
关键词 analytical mechanics Birkhoff system stability In 1927 American mathematician Birkhoff GD obtained a kind of dynamical equationswhich were more general than the Hamilton's equations in his well -known work ' DynamicalSystems' [1] In 1978. American ph
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Soil erosion of unpaved loess roads subjected to an extreme rainstorm event: a case study of the Jiuyuangou watershed on the Loess Plateau, China 被引量:11
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作者 YANG Bo WANG Wen-long +5 位作者 GUO Ming-ming GUO Wen-zhao WANG Wen-xin KANG Hong-liang ZHAO Man CHEN Zhuo-xin 《Journal of Mountain Science》 SCIE CSCD 2019年第6期1396-1407,共12页
Rainfall can cause serious soil loss in the Loess Plateau hilly and gully region, but little focus has been placed on the extreme rainstorm effects on unpaved loess road soil erosion. A field survey method was used to... Rainfall can cause serious soil loss in the Loess Plateau hilly and gully region, but little focus has been placed on the extreme rainstorm effects on unpaved loess road soil erosion. A field survey method was used to investigate the erosional effects of the '7·26' heavy rainfall event on unpaved loess roads in the Jiuyuangou watershed of the Loess Plateau, China. The results showed that the average and maximum widths of the eroded gullies that formed on the unpaved roads were 0.65-1.48 m and 1.00-3.60 m, respectively. The average and maximum depths of theeroded gullies were 0.42-1.13 m and 0.75-4.30 m, respectively. The average width-to-depth ratio was 1.31, indicating that the widening effect was greater than the downcutting effect in the eroded gullies. In addition, the gully density ranged from 0.07 to 0.29 m m-2, and the road surface dissection degree ranged from 0.03 to 0.41 km2 km-2. Eroded gullies generally developed at the slope toe of the cut bank side. The average eroded gully width and depth at turns in the road were 1.47-2.64 times and 1.30-3.47 times greater, respectively, than those in other road sections. The road erosion modulus increased from the upper section to the lower section of the roads. The average road erosion modulus of the study catchment was 235,000 t km-2. Turns in the road were associated with collapses, sinkholes and other gravitational erosion phenomena. The amount of road erosion under extreme rainfall conditions is mainly related to the interactions among road length, width, slope and soil bulk density. Our results provide a useful reference for developing further measures for preventing road erosion on the Loess Plateau. 展开更多
关键词 Road erosion '7·26' EXTREME rainstorms LOESS Plateau GULLY development
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The tumor-selective over-expression of the human Hsp 70 gene is attributed to the aberrant controls at both initiation and elongation levels of transcription 被引量:13
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作者 LING CAI, JING DE ZHU,The State-key Laboratory for Oncogenes and Related Genes, Shanghai Cancer Institute, LN 25/2200, Xie-tu Road, Shanghai 200032, China 《Cell Research》 SCIE CAS CSCD 2003年第2期93-109,共17页
The tumor selective over-expression of the human Hsp70 gene has been well documented in human tumors,linked to the poor prognosis,being refractory to chemo-and radio-therapies as well as the advanced stage of tumorous... The tumor selective over-expression of the human Hsp70 gene has been well documented in human tumors,linked to the poor prognosis,being refractory to chemo-and radio-therapies as well as the advanced stage of tumorous lesions in particular.However,both the nature and details of aberrations in the control of the Hsp70 expression in tumor remain enigmatic.By comparing various upstream segments of the Hsp70 gene for each''s ability to drive the luciferase reporter genes in the context of the tumor cell lines varying in their p53 status and an immortal normal liver cell line,we demonstrated in a great detail the defects in the control mechanisms at the both initiation and elongation levels of transcription being instrumental to the tumor selective profile of its expression.Our data should not only offer new insights into our understanding of the tumor specific over-expression of the human Hsp70 gene,but also paved the way for the rational utilization of the tumor selective mechanism with the Hsp70 at the central stage fortargeting the therapeutic gene expression to human tumors. 展开更多
关键词 Hsp 70 TUMOR transcription elongation 5' UTR. Over-expression.
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Hydrothermal Syntheses and Crystal Structures of Six Complexes Constructed from 1,3,5-Benzenetricarboxylic Acid and 4'-(4-Pyridyl)-2,2':6',2''-terpyridine Mixed Ligands 被引量:4
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作者 乔宇 王炫博 +4 位作者 周艳凤 刘力辉 车广波 刘春波 刘晓腾 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第8期1381-1394,共14页
Six new transition metal complexes, [Zn(HBTC)(PYTPY)]n·n PYTPY(1), [Cu(HBTC)(PYTPY)]n·n PYTPY(2), [Co(HBTC)(PYTPY)]n·n DMF(3), [Mn(HBTC)(PYTPY)]n·n DMF(4), [Cd(HBTC)(PYTP... Six new transition metal complexes, [Zn(HBTC)(PYTPY)]n·n PYTPY(1), [Cu(HBTC)(PYTPY)]n·n PYTPY(2), [Co(HBTC)(PYTPY)]n·n DMF(3), [Mn(HBTC)(PYTPY)]n·n DMF(4), [Cd(HBTC)(PYTPY)(H2O)]n·2nH2O(5), and [Co(HBTC)(PYTPY)(H2O)2](6),(H3BTC = 1,3,5-benzenetricarboxylic acid, PYTPY = 4'-(4-pyridyl)-2,2':6',2''-terpyridine, DMF = N,N?-dimethylformamide), have been synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. Complexes 1~5 all feature one-dimensional chain structures, and complex 6 exhibits a zero-dimensional structure. Complexes 1~5 present three-dimensional(3D) supramolecular frameworks via π-π stacking interactions, whenas 6 has also a 3D supramolecular structure assembled by hydrogen bonding. Meanwhile, complexes 1 ~ 6 exhibit the thermal stabilities and photoluminescent properties. 展开更多
关键词 transition metal complex 1 3 5-benzenetricarboxylic acid 4'-(4-pyridyl)-2 2' 6' 2''-terpyridine crystal structure
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Transition from Metastablity to Instability in Dynamics for the Precipitation of δ'(Al_3Li) 被引量:7
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作者 Xiaoling Li, Zheng Chen, Bing Liu, Yongxin Wang Department of Materials Science and Engineering, Northwestern Polytechnical University. Xi’an, 710072, China 《Rare Metals》 SCIE EI CAS CSCD 2001年第4期240-247,共8页
A computer simulation study on dynamics for the precipitation of δ'(Al_3Li) ordered particles from a disor- dered matrix (α) in binary Al-Li alloys is performed using the microscopic Langevin equation. A unique ... A computer simulation study on dynamics for the precipitation of δ'(Al_3Li) ordered particles from a disor- dered matrix (α) in binary Al-Li alloys is performed using the microscopic Langevin equation. A unique precipitation mechanism is found near the ordering spinodal line. Different from the classical nucleation mechanism in the me- tastable region and the congruent ordering followed by spinodal decomposition in the instable region, a nonstoichi- ometric single ordered phase with composition fluctuations is formed by non-classical nucleation, and this ordered phase decomposes spinodally. It can be concluded that the precipitation dynamics of δ' phase from metastability to instability is gradual, and no sharp transition occurs near the mean-field spinodal line as the mean-field theory pre- dicts. 展开更多
关键词 δ'(Al_3Li) precipitation dynamics non-classical nucleation gradual transition
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Clinical Implication of the Changes of cAMP, TXA_2 and PGI_2 in CSF of Asphyxiated Newborns 被引量:5
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作者 刘汉楚 常立文 +2 位作者 陈晔 夏世文 张晓慧 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2003年第2期195-197,200,共4页
To evaluate the changes of 3', 5'-cyclic adenosine monophosphate (cAMP), thrombox-ane A2(TXA2) and prostacyclin (PGI2) in cerebrospinal fluid (CSF) in the asphyxiated newborn and explore their roles in hypoxic... To evaluate the changes of 3', 5'-cyclic adenosine monophosphate (cAMP), thrombox-ane A2(TXA2) and prostacyclin (PGI2) in cerebrospinal fluid (CSF) in the asphyxiated newborn and explore their roles in hypoxic-ischamic brain damage (HIBD). Thirty-six full term newborns were divided into 3 groups, including 12 with moderate-severe hypoxic-ischaemic encephalopathy (HIE), 13 with mild HIE, 11 without HIE (control group). The levels of cAMP, TXB2(TXA2 metabolite) and 6-keto-PGF1α(PGI2 metabolite) in CSF and plasma were measured 36-72 h after birth by RIA, and the concentrations were expressed as nM/L (cAMP), ng/L(TXB2 and 6-keto-PGF1α). The infants were followed-up at 6 and 12 month of age and Mental Development Index (MDI) and Psychomotor Development Index (FDD were measured using Bayley Scales of Infant Development (BSID). The CSF cAMP level in moderate-severe HIE group was 8. 60±2. 40, significantly lower than that of the mild HIE group (14. 83±2. 84) and the control group (24. 43±2. 39)(for both P<0. 01). The levels of TXB2 and 6-keto-PGF1α in CFS in the moderate-severe HIE group (206. 06±29. 74, 168. 47± 23. 02, respectively) were significantly higher than in the mild HIE group (83. 37±28. 57, 131. 42± 16. 57, respectively, P<0. 01) and the control group (41. 77±21. 58, 86. 23±13. 05, respectively, P<0. 01). The level changes of cAMP,TXB2 and 6-keto-PGF1α in plasma in all groups were similar to those in CSF, but no significant difference was found between mild HIE group and the control group (P>0. 05). The follow-up results showed that MDI and PDI of the moderate-severe HIE group were the lowest (84. 79±13. 34, 83. 50±13. 28, respectively), followed by mild HIE group (102.19±7. 02, 99. 94±9. 08, respectively) , with the control group being the highest (116. 63± 12.08, 116. 69±10. 87, respectively). Univariate analysis showed some significant difference (the moderate-severe HIE group vs. the mild HIE group or the control group, P<0. 01; the mild HIE group vs. the control group P<0. 05). The results suggested that the concentration of cAMP, TXA2 and T/K ratio in CSF after neonatal asphyxia might be sensitive markers in evaluating the severity of brain damage in early stage and predicting the future outcome. 展开更多
关键词 neonate infant ASPHYXIA 3' 5'-cyclic adenosine monophosphate prostacyclins thromboxane A2 cerebrospinal fluid
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Application of Big Data in Agricultural Informationization in Shandong Province under the Background of "Internet +" 被引量:1
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作者 Xinling GAN Yong LI 《Asian Agricultural Research》 2019年第4期1-3,共3页
This paper explains the basic concepts of " Internet + " and big data,analyzes the main problems in the application of big data technology in agricultural informationization of Shandong Province,summarizes c... This paper explains the basic concepts of " Internet + " and big data,analyzes the main problems in the application of big data technology in agricultural informationization of Shandong Province,summarizes corresponding solutions from the aspects of government guidance,financial input,open sharing of agricultural big data,big data storage and processing,data mining,etc.,and prospects the application trend of big data technology in agricultural informationization to achieve the connotative development of agriculture in Shandong Province. 展开更多
关键词 AGRICULTURAL informationization 'Internet +' BIG DATA
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Sequence variability of the 5, UTR in isolates of hepatitis C virus in China 被引量:1
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作者 Yuan-Ding Chen Ming-Ying Liu +6 位作者 Wen-Lin Yu Jia-Qi Li Mei Peng Qing Dai Jun Wu Xiao Liu Zhen-Quan Zhou the Key Laboratory, Institute of Medical Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Kunming 650118, China and Kunming Hospital for Infectious Diseases, Kunming 650041, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2002年第4期541-552,共12页
Background: Hepatitis C virus infection is a great is- sue in China; however, there is very little informa- tion on genotyping investigations based on sequence variability in the 5' untranslated (5'UTR) report... Background: Hepatitis C virus infection is a great is- sue in China; however, there is very little informa- tion on genotyping investigations based on sequence variability in the 5' untranslated (5'UTR) reported. The present study was to define the sequence varia- bility based on the sequence divergences of the 5' UTR of the virus. Methods: Sequences of 91 isolates from patients with chronic hepatitis C from Yunnan, southwest China, were sequenced and genotypes were defined accord- ing to the sequence divergences of the 5' UTR of the virus. Results: Eighty-six isolates were classified into 3 clades (previously termed groups or major types) by the methods proposed by Chan et al in 1992 and phy- logenetic analysis based on nucleotide sequence diver- gences within the 5' UTR. Fifty-six percent of the i- solates were classified into clade 3, 35% into clade 1, and 34.9% into clade 2. New genotypes 1f, 2h, 3h and 3i were defined. In addition, 3 novel sequences were discovered, respectively with an 18-nt sequence deletion (corresponding to nucleotide position -173 to -156), a 28-nt sequence insertion, and a 40-nt se- quence insertion, between -56 and -55. Of these i- solates, 56% possessed a 'G' at position -66 in place of the 'T' that is present in all previously re- ported sequences. Conclusions: These HCV variants, evolved or re- mained in this area, may be of great significance in diagnosis and treatment of hepatitis C patients. 展开更多
关键词 hepatitis C pepatitis C virus 5' UTR sequence variability GENOTYPES China
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Study on the Post-evaluation of Environmental Planning Based on Logical Framework Approach 被引量:2
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作者 CHEN Yu-xian DONG Ze-qin 《Meteorological and Environmental Research》 CAS 2011年第2期1-5,9,共6页
[Objective] The aim was to conduct post-evaluation on environmental planning by means of logical framework approach. [Method] Taking environmental planning during '11th Five-year Plan' in a certain province fo... [Objective] The aim was to conduct post-evaluation on environmental planning by means of logical framework approach. [Method] Taking environmental planning during '11th Five-year Plan' in a certain province for example, by means of logical framework approach (LFA), the post-evaluation on environmental planning was carried out from the aspects of evaluation content, index system, implementation steps, evaluation feedback and input-output analysis of environmental planning. [Result] The post-evaluation on environmental planning by means of LFA achieved expected purpose and various indexes at different stages of environmental planning was assessed, and then corresponding countermeasures were put forward according to the problems which were found by problem tree of environmental planning project. [Conclusion] The study could provide theoretical references for the post-evaluation on environmental planning in future. 展开更多
关键词 Logical framework approach Environmental planning during '11th Five-year Plan' POST-EVALUATION China
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Synthesis,Crystal Structure,and Magnetic Property of One 3D Nickel Coordination Polymer Based on 2-Hydroxy-5-(3',5'-terephthalic acid)Pyridine and 1,4-Bis(1-imdazoly)benzene 被引量:1
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作者 TANG Pei-Qin HAO Lu-Jiang +3 位作者 FAN Li-Ming LIU Xin-Zheng LI Bin ZHANG Xiu-Tang 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第10期1519-1524,共6页
One novel nickel coordination polymer, {[Ni(OTP)(bib)1.5(H2O)]·2H2O}n(1, H2 OTP = 2-hydroxy-5-(3',5'-terephthalic acid) pyridine, bib = 1,4-bis(1-imdazoly)benzene), has been synthesized and characte... One novel nickel coordination polymer, {[Ni(OTP)(bib)1.5(H2O)]·2H2O}n(1, H2 OTP = 2-hydroxy-5-(3',5'-terephthalic acid) pyridine, bib = 1,4-bis(1-imdazoly)benzene), has been synthesized and characterized by elemental analysis(EA), IR, powder X-ray diffraction(PXRD), and thermogravimetric(TG) analyses. The crystal of 1 crystallizes in monoclinic, space group P21/n with a = 12.2860(5), b = 13.8246(6), c = 19.0140(8) A, β = 104.3870(1)°, V = 3128.2(2) A3, Z = 4, C32H28N7 Ni O8, Mr = 697.32, Dc = 1.481 g/cm^3, F(000) = 1444 and μ(Mo Kα) = 0.684 mm-1. The final R = 0.0704 and w R = 0.1764 for 5485 observed reflections with I 2σ(I) and R = 0.1087 and wR = 0.2010 for all data. Topology analysis reveals that complex 1 is a 3D 2-fold interpenetrated {4^4·6^6}-nov net based on the 1D [Ni(OTP)]n chain and the 2D [Ni2(bib)3]n sql sheet. And the variable-temperature magnetic susceptibility measurements exhibit weak antiferromagnetic coupling interaction. 展开更多
关键词 2-hydroxy-5-(3' 5'-terephthalic acid)pyridine 1 4-bis(1-imdazoly)benzene NICKEL topology magnetic property
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Synthesis and Properties of D-Thymidylyl (3'→5')L-Thymidine (D/L-TpT)
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作者 Xiao Hui GU Yi Bing ZHANG Yao Quan CHEN(State Key Laboratory of Bio-organic and Natural Products Chemistry, Shanghai Instituteof Organic Chemistry, Chinese Academy of Sciences. 354 Fenglin Road. Shanghai 200032) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第9期741-744,共4页
The synthesis and properties of D-thymidylyl (3'→5')L-thymidine (D/L-TpT) aredescribed.
关键词 Antisense oligonucleotides anticancer SYNtheSIS D-thymidylyl (3'→5')L-thymidine.
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Infinite Three-Dimensional Coordination Polymers: Synthesis and Structures of [Cd (4,4'-bpy)_2 (H_2O)_2]_n (pic)_(2n),[Zn (4,4'-bpy)_2 (H_2O)_2]_n(pic)_(2n) (H_2O)_(2n), and [Zn (4,4'-bpy)_2 (H_2O)_2]_n (4,4'-bpy)_n(H_2O)_n (pic)_(2n) 被引量:1
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作者 Fu Pei LIANG~1 Zi Lu CHEN~1 +2 位作者 Rui Xiang HU~1 Hong LIANG~1 Zhao Hui ZHOU~2 (1 Department of Chemistry. Guangxi Normal University: Guilin 541004 2 Department of Chemistry. Xiamen University. Xiamen 361005) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第4期369-372,共4页
Three Complexes of the formula [Cd (4,4'-bpy)_2 (H_2O)_2]_n. (pic)_(2n) (1) [Zn (4,4'-bpy)_2 (H_2O)]_n (4,4'-bpy)_n(H_2O)_n (pic)-(2n) (2) and [Zn (4,4'-bpy)_2 (H_2O)]_n (4,4'-bpy)_n (pic)-(2n)(H_... Three Complexes of the formula [Cd (4,4'-bpy)_2 (H_2O)_2]_n. (pic)_(2n) (1) [Zn (4,4'-bpy)_2 (H_2O)]_n (4,4'-bpy)_n(H_2O)_n (pic)-(2n) (2) and [Zn (4,4'-bpy)_2 (H_2O)]_n (4,4'-bpy)_n (pic)-(2n)(H_2O)_n (3) (4.4'-bpy = 4.4'-bipyridine. pic = picric anion ) have been synthesized and characterized by elemental analysis and single-crystal x-ray diffraction. They all have infinite three-dimensional network structure. crystallizing in the monoclinic space group C2/c (1) and Cc (2.3). 展开更多
关键词 Clathration. 4. 4' - bipyridine. picric anion. three - dimensional network.
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The Odour of Cheese语言风格及修辞特色赏析
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作者 彭继玉 《吉首大学学报》 1993年第4期98-100,共3页
【正】 J·K·杰罗姆(Jerome L.Jerome)是一位以其语言跌宕多姿,文笔幽默风趣而闻名于世的英国作家.他的《三人同乘一条船》(ThreeMen in a Boat)发表于1889年.这部作品的问世使他一举成名,“奶酪气味”(The Odour ofCheese)就... 【正】 J·K·杰罗姆(Jerome L.Jerome)是一位以其语言跌宕多姿,文笔幽默风趣而闻名于世的英国作家.他的《三人同乘一条船》(ThreeMen in a Boat)发表于1889年.这部作品的问世使他一举成名,“奶酪气味”(The Odour ofCheese)就是“三人同乘一条船”当中的一章.在这一章中,作者巧妙地应用各种修辞手法,把他携奶酪从利物普市到达伦敦的一路“愉快” 展开更多
关键词 英国 杰罗姆 修辞 数字 章法 '奶酪气味' 语言风格 《三人同乘一条船》
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Molecular and Crystal Structure of 4-Amino-4'-Nitrodiphenyl Ether
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作者 赵波 祁铁流 郁开北 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第1期34-36,共3页
The title compound (C 12 H 10 N 2O 3, M r =230.22) is monoclinic, space group P2 1/c with unit cell of a=7.234 (1), b=8.999 (1), c=16.907(2) ; β=102.47°, V=1099.6(2) 3, Z=4, D c= 1.391g/... The title compound (C 12 H 10 N 2O 3, M r =230.22) is monoclinic, space group P2 1/c with unit cell of a=7.234 (1), b=8.999 (1), c=16.907(2) ; β=102.47°, V=1099.6(2) 3, Z=4, D c= 1.391g/cm 3; λ (Mo Kα )=0.71073 , μ =0.102mm -1 , F (000)=480, final R=0.0322, wR= 0.0770 for 1937 observed reflections [ I>2σ(I) ]. Structure analyses reveal that the two benzene rings are almost perpendicular and the bond angle between the two benzene rings is 118.44°. 展开更多
关键词 amino 4' nitrodiphenyl ether crystal structure molecular structure
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Acute Toxicity Effects of 2,2',4,4',5,5'-Hexabromodiphenyl Ether on Chlorella vulgaris
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作者 Shunlong MENG Xi Chen +5 位作者 Liping QIU Chao SONG Limin FAN Yao ZHENG Jiazhang CHEN Pao XU 《Agricultural Biotechnology》 CAS 2020年第3期115-118,共4页
[Objectives] This study was conducted to investigate the toxic effects of 2,2',4,4',5,5'-hexabromobiphenyl ether on Chlorella vulgaris and provide basic data for protecting aquatic ecosystems. [Methods] Th... [Objectives] This study was conducted to investigate the toxic effects of 2,2',4,4',5,5'-hexabromobiphenyl ether on Chlorella vulgaris and provide basic data for protecting aquatic ecosystems. [Methods] The acute toxicity effects of 2,2',4,4',5,5'-hexabromodiphenyl ether on C. vulgaris was investigated by the semi-static water contacting acute toxicity method. [Results] The 48,72 and 96 h-EC(50) of 2,2',4,4',5,5'-hexabromodiphenyl ether to C. vulgaris were23. 58,18. 71 and 14. 75 μg/L,respectively,and the safe concentration of 2,2',4,4',5,5'-hexabromodiphenyl ether to C. vulgaris was 1. 475μg/L. For the water solubility of 2,2',4,4',5,5'-hexabromodiphenyl ether is extremely low( 1 μg/L),it could not cause the acute poisoning death of C. vulgaris. According to the grading standards for the assessment of the toxicity on algae,2,2',4,4',5,5'-hexabromodiphenyl ether was extremely highly toxic to C. vulgaris. [Conclusions]The extremely high toxicity of 2,2',4,4',5,5'-hexabromodiphenyl ether to C. vulgaris shows that it has heavy potential harm to aquatic ecosystems and the maximum residue limit standards of 2,2',4,4',5,5'-hexabromodiphenyl ether in water should be formulated to better protect aquatic ecosystems. 展开更多
关键词 2 2' 4 4' 5 5'-Hexabromodiphenyl ether Acute toxicity Chlorella vulgaris 96 h EC(50)
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Analysis on the Climatic Characteristics of Temperature in "24 Solar Terms" in Liaoning Province
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作者 HOU Ya-hong1,LU Shuang2,ZHANG Rui2 1.Liaoning Meteorological TV Center,Shenyang 110016,China 2.Dongling District Meteorological Bureau in Shenyang City,Shenyang 110168,China 《Meteorological and Environmental Research》 CAS 2011年第3期36-38,共3页
[Objective] The aim was to analyze the climatic characteristics of temperature in '24 solar terms' in Liaoning Province.[Method] Based on the daily temperature data from 56 stations in Liaoning Province from 1... [Objective] The aim was to analyze the climatic characteristics of temperature in '24 solar terms' in Liaoning Province.[Method] Based on the daily temperature data from 56 stations in Liaoning Province from 1951 to 2009,the climatic characteristics of temperature in '24 solar terms' in Liaoning Province in recent 59 years were analyzed.[Result] The time series of average temperature in '24 solar terms' in Liaoning Province showed quasi normal distribution from 1951 to 2009,namely single peak type.Great Heat meant the hottest time within one year,and next came Slight Heat,while Slight Cold was the coldest time within one year,and Great Cold took the second place.Among 24 solar terms,temperature increased most obviously in Tomb-sweeping Day,with the increase of 4.9 ℃,while temperature decreased most greatly in the Beginning of Winter,with the decrease of 5.1 ℃.There was obvious decadal variation in average temperature in Slight Heat,Great Heat,Slight Cold,Great Cold and the End of Heat which were closely related to temperature,and average temperature went up with time.From 1951-1980 to 1981-2009,average temperature in 22 solar terms showed increase trend,and there was no change in one solar term,while average temperature in one solar term decreased slightly,and average temperature in 24 solar terms increased by 0.66 ℃.[Conclusion] The study could provide scientific reference for meteorological service. 展开更多
关键词 '24 solar terms' TEMPERATURE Climatic characteristics Liaoning Province China
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Search for New AntiphytovirucidesⅣ.Synthesis of 2-(2'-Hydroxyphenyl)-5(6)-substituted benzimidazole Derivatives
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作者 Huang Xiaoling, Jiang Hong, Qu Fanqi, Zhong Min Department of Chemistry, Wuhan University, Wuhan 430072,China National Laboratory of Elemento Organic Chemistry, Nankai University, Tianjin 300071,China 《Wuhan University Journal of Natural Sciences》 CAS 1997年第1期70-72,共3页
A convenient method to synthesize substituted 2 (2' hydroxyphenyl) benzimidazoles is reported. Six title compounds have been synthesized by the reaction of salicylic acid and 4 substituted o phenylene... A convenient method to synthesize substituted 2 (2' hydroxyphenyl) benzimidazoles is reported. Six title compounds have been synthesized by the reaction of salicylic acid and 4 substituted o phenylenediamine in the presence pyridine POCl 3 . Three compounds were tested as plant virucide against tobacco mosaic virus and they exhibited some activities. 展开更多
关键词 substituted 2 (2' hydroxyphenyl)benzimidazole synthesis plant virucide CONDENSATION
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Analysis of the 3' Variable Region of Cytotoxin-Associated Gene A (<i>cagA</i>) in <i>Helicobacter pylori</i>Isolates in China
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作者 Boqing Li Donglong Du +3 位作者 Wanju Sun Qizhi Cao Zhen Zhang Zhenzhen Du 《Pharmacology & Pharmacy》 2013年第5期13-18,共6页
Infection by the bacterium Helicobacter pylori is a putative cause of various gastric disorders, including gastric adenocarcinoma. Incident rates are associated with variants of the H. pylori virulence factor cytotoxi... Infection by the bacterium Helicobacter pylori is a putative cause of various gastric disorders, including gastric adenocarcinoma. Incident rates are associated with variants of the H. pylori virulence factor cytotoxin-associated gene A protein (CagA), encoded by the gene cagA. However, these variants have not been characterized in China, where gastric cancer is common. We investigated the diversity of CagA variants in H. pylori strains isolated from a Chinese population. The 3' variable region of cagA genes from 66 clinical isolates in China were amplified by polymerase chain reaction, sequenced, aligned, and analyzed. All 66 H. pylori strains were CagA-positive, of which 93.9% were East Asian type and the tyrosine phosphorylation motifs (TPMs) were EPIYA-ABD. The remainder was Western type, in which TPMs were EPIYA-ABC. Interestingly, two of sixty-two strains (3.2%) of the East Asian type were mutated into ESIYA-B, whereas all four Western type (100%) strains were mutated into EPIYT-B. Both of the two strains with Western-type CagA obtained from gastric cancer patients contained a distinguished mutation on the first residue following the EPIYA site in the EPIYA-A motif. The predominant CagA type in these H. pylori strains isolated from Chinese patients in China was East Asian, with TPMs EPIYA-ABD, and there existed mutations in both the East Asian and Western type CagA. 展开更多
关键词 HELICOBACTER pylori CAGA 3' Variable Region China GASTRITIS Gastric Cancer
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