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Mechanics and the evolution and functional morphology of conchostracan carapace 甲壳的力学、演化及功能形态
Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences Pub Date : 1989-05-10 DOI: 10.1360/YB1989-32-5-631
Wang Si-en
{"title":"Mechanics and the evolution and functional morphology of conchostracan carapace","authors":"Wang Si-en","doi":"10.1360/YB1989-32-5-631","DOIUrl":"https://doi.org/10.1360/YB1989-32-5-631","url":null,"abstract":"Conchostracans, with a laterally compressed body enclosed between two symmetric valves, live swimming in fresh or brackish water. The carapace valve has a number of growth bands with various sculptures. The general trend of sculptural evolution is from smooth to punctate-minute polygon-medium reticulation-large reticulation, while these punctate, polygonal and various reticulate patterns may separately develop into various radial ridges. The development of sculpture can be well explained by mechanical principle. Functional morphology of carapace is discussed in the light of mechanics in this paper.","PeriodicalId":223601,"journal":{"name":"Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122475569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 6
Studies on the crystal structure of A1-(L-tryptophan) insulin at 2.1 A resolution. 2.1 A分辨率下A1-(l -色氨酸)胰岛素晶体结构的研究。
Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences Pub Date : 1988-12-10 DOI: 10.1360/YB1988-31-12-1426
Wang Zl, Liang Dc
{"title":"Studies on the crystal structure of A1-(L-tryptophan) insulin at 2.1 A resolution.","authors":"Wang Zl, Liang Dc","doi":"10.1360/YB1988-31-12-1426","DOIUrl":"https://doi.org/10.1360/YB1988-31-12-1426","url":null,"abstract":"In order to study the biological effect of alterations to the N-terminus of the insulin A-chain, we have determined the crystal structure of A1-(L-Trp) insulin and discovered that it belongs to the trigonal system with space group R3. The parameters of the unit cell are a = b = 80.3A, c = 37.5A. The model was adjusted and refined by using a stereochemically-restrained least squares program, assisted by manual revision of the model based on the difference Fourier map, to a final R-factor of 0.195. The main and side chains of both A1-(L-Trp) residues in the asymmetric unit are well ordered. It was found that the A1-Trp residue of molecule I occupied two distinct positions. We have proposed from the results of the three-dimensional structure that the 4-zinc insulin hexameric form is a stored state of insulin molecules in a conformation of low activity. The structural details of the insulin molecule and its structure and function relationship have also been discussed.","PeriodicalId":223601,"journal":{"name":"Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124749937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
二元六相( n +4)多体系的八点直线网图——I.由九点封闭网图推导 二元六相( n +4)多体系的八点直线网图——I.由九点封闭网图推导
Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences Pub Date : 1988-12-10 DOI: 10.1360/ZB1988-18-12-1334
程伟基 郭其悌
{"title":"二元六相( n +4)多体系的八点直线网图——I.由九点封闭网图推导","authors":"程伟基 郭其悌","doi":"10.1360/ZB1988-18-12-1334","DOIUrl":"https://doi.org/10.1360/ZB1988-18-12-1334","url":null,"abstract":"二元六相多体系的九点封闭网图包含了两种基本类型的非直线部分。只有除去某九点封闭网图所包含的全部非直线部分所共享的一个无变度点,才可能获得1张八点直线网图。总共导出了二元六相多体系的67张不同的八点直线网图。它们分属31个不同的八点直线网(即31个不同的八点集合)。由此,证明了过去关于二元六相多体系仅有1张八点直线网图的结论是错误的。","PeriodicalId":223601,"journal":{"name":"Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121144038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
TRANSPORTATION THEORY OF MULTIPLE SCATTERING AND ITS APPLICATION TO SEISMIC CODA WAVES OF IMPULSE SOURCE 多次散射输运理论及其在脉冲震源尾波中的应用
Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences Pub Date : 1988-12-10 DOI: 10.1360/YB1988-31-12-1503
Shang Tieliang, Gao Longsheng
{"title":"TRANSPORTATION THEORY OF MULTIPLE SCATTERING AND ITS APPLICATION TO SEISMIC CODA WAVES OF IMPULSE SOURCE","authors":"Shang Tieliang, Gao Longsheng","doi":"10.1360/YB1988-31-12-1503","DOIUrl":"https://doi.org/10.1360/YB1988-31-12-1503","url":null,"abstract":"The energy distribution of elastic waves in an infinite elastic medium with uniformly and randomly distributed scatterers has been researched. The scattering process is assumed to be isotropic and without conversions between wave types. We get the equation on the distribution of energe density in time and space covering single as well as multiple scattering. Taking physical symmetry of the field into account, it can be simplified. In the case of small earthquakes, the energy source of elastic waves can be assumed as a short pulse emitted isotropically at t=0. The first-order approximate solution in the 3-dimensional space can be obtained, and it is equivalent to Sato's solution for single scattering. In the 2-dimensional space the complete analytical solution has been derived by the mathematical inductance which leads to a conclusion that the codas of surface waves can give the Q-factor related to intrinsic absorption. The equation obtained in this paper is more general.","PeriodicalId":223601,"journal":{"name":"Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126881278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 100
新颖的三价磷化合物的一锅反应研究——I.二烷基亚磷酸酯与β-硝基苯乙烯衍生物的一步加成、还原、关环反应的研究 新颖的三价磷化合物的一锅反应研究——I.二烷基亚磷酸酯与β-硝基苯乙烯衍生物的一步加成、还原、关环反应的研究
Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences Pub Date : 1988-11-10 DOI: 10.1360/ZB1988-18-11-1137
李玉桂, 王国洪, 张殿坤, 缪方明, 刘小兰, 曹金鸿, 郭杭州
{"title":"新颖的三价磷化合物的一锅反应研究——I.二烷基亚磷酸酯与β-硝基苯乙烯衍生物的一步加成、还原、关环反应的研究","authors":"李玉桂, 王国洪, 张殿坤, 缪方明, 刘小兰, 曹金鸿, 郭杭州","doi":"10.1360/ZB1988-18-11-1137","DOIUrl":"https://doi.org/10.1360/ZB1988-18-11-1137","url":null,"abstract":"本文首次研究了O,O-二烷基亚磷酸酯在三甲基氯硅烷和缚酸剂的共同催化下与取代β-硝基苯乙烯的反应。控制适当条件几乎可以专一地分别得到三种产物,在很温和的条件下发生磷原子上Arbuzov重排的同时进行了加成、还原、关环的一锅反应,得到含有P—C键的1-羟基吲哚类新化合物Ⅱ a-h 。其结构已由元素分析、IR、 1 HNMR和MS证实,代表化合物Ⅱ h 的晶体结构经X-ray确证。并用 31 PNMR定量地研究了原料的摩尔比、溶剂、苯环上取代基、缚酸剂、反应时间、温度等对生成产物分布的影响。初步探讨了反应机理,生物活性正待测定。","PeriodicalId":223601,"journal":{"name":"Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115812587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
福建莆田海岸沙丘岩——I.沉积构造与古风 福建莆田海岸沙丘岩——I.沉积构造与古风
Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences Pub Date : 1988-11-10 DOI: 10.1360/ZB1988-18-11-1196
沙庆安V. Goldsmith王绍鸿孙亨伦张景文张德泉 赵希涛
{"title":"福建莆田海岸沙丘岩——I.沉积构造与古风","authors":"沙庆安V. Goldsmith王绍鸿孙亨伦张景文张德泉 赵希涛","doi":"10.1360/ZB1988-18-11-1196","DOIUrl":"https://doi.org/10.1360/ZB1988-18-11-1196","url":null,"abstract":"福建莆田后石井海岸沙丘岩由三个沙脊组成。本文记述了这些沙脊的形状与沉积构造,并在讨论其成因的基础上重建了古沙丘类型与古风向。本文认为,它们是中全新世末盛行的东北季风吹扬海滩沉积物再堆积所形成的有植被沙丘与风影沙丘,古今风向未发生明显的变化。","PeriodicalId":223601,"journal":{"name":"Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115801883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
上海城市气候中的“五岛”效应 上海城市气候中的“五岛”效应
Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences Pub Date : 1988-11-10 DOI: 10.1360/ZB1988-18-11-1226
周淑贞
{"title":"上海城市气候中的“五岛”效应","authors":"周淑贞","doi":"10.1360/ZB1988-18-11-1226","DOIUrl":"https://doi.org/10.1360/ZB1988-18-11-1226","url":null,"abstract":"本文从人为条件(城市下垫面性质的改变、人为热和污染物的排放等)与天气条件(大尺度环流微弱、局地天气形势等)两方面的结合上,应用气象卫星资料、回归统计分析、典型个例分析与长期气候统计分析等方法,阐明上海城市热岛、干岛、湿岛、雨岛和混浊岛等五岛效应的形成过程、特征以及它们之间相互制约、相互联系的关系。这对论证人类活动(通过城市化)对气候的影响,防治城市气候恶化,进行城市天气气候预报和城市规划都有重要意义。","PeriodicalId":223601,"journal":{"name":"Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124346179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
三核锇原子簇中 μ,η 2 -乙烯配位基顺反异构化及其反应动力学研究 三核锇原子簇中 μ,η 2 -乙烯配位基顺反异构化及其反应动力学研究
Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences Pub Date : 1988-11-10 DOI: 10.1360/ZB1988-18-11-1147
A. J. D. B. D. 刘家础
{"title":"三核锇原子簇中 μ,η 2 -乙烯配位基顺反异构化及其反应动力学研究","authors":"A. J. D. B. D. 刘家础","doi":"10.1360/ZB1988-18-11-1147","DOIUrl":"https://doi.org/10.1360/ZB1988-18-11-1147","url":null,"abstract":"含氢原子簇化合物H 2 Os 3 (CO) 10 与乙炔反应生成顺式加成物[Os 3 H( μ,η 2 -CH=CH 2 )(CO) 10 ]。本文首次报道高含量氘代原子簇D 2 Os 3 (CO) 10 与乙炔反应生成合乙烯配位基的氘代原子簇[Os 3 D( μ,η 2 -CH=CHD)(CO) 10 ],H 2 Os 3 (CO) 10 与氘代乙炔反应生成[Os 3 H( μ,η 2 -CD=CDH)(CO) 10 ],它们在微量亲核试剂吡啶作用下发生 μ,η 2 -乙烯配位基的顺反异构反应。本文用同位素氘代和 1 H, 2 H NMR动态波谱联用方法,研究了上述反应和异构化过程,提出了顺反异构化的核磁共振动态波谱证据、反应机理和动力学数据。","PeriodicalId":223601,"journal":{"name":"Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121836910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
小麦条锈病对小麦产量影响的研究——II.病害对小麦叶片光合作用的影响初探 小麦条锈病对小麦产量影响的研究——II.病害对小麦叶片光合作用的影响初探
Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences Pub Date : 1988-11-10 DOI: 10.1360/ZB1988-18-11-1174
曾士迈 杨小冰
{"title":"小麦条锈病对小麦产量影响的研究——II.病害对小麦叶片光合作用的影响初探","authors":"曾士迈 杨小冰","doi":"10.1360/ZB1988-18-11-1174","DOIUrl":"https://doi.org/10.1360/ZB1988-18-11-1174","url":null,"abstract":"利用红外线气体分析仪测定了冬小麦燕大1817和东方红3号在受到条锈菌(Puccinia striiformis West)侵染后叶片光合作用的变化。证明严重度S越高,残余健部光合作用极大值 P ′ max 越低,其关系为 P ′ max = P ′ max (1-0.826*S)。根据试验数据推导建立了条锈病导致的光合产物降低率预测模型: L 光合 =1-( P ′ max + I 1 α )/( P ′ max + I 1 α )(1-bS)(1-S),和理论模型 L 光合 =aS~n,n=f( P ′ max / P ′ max )。最后讨论了 L 光合 与验经产量损失模型的关系。","PeriodicalId":223601,"journal":{"name":"Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124958977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
1-取代苯磺酰基-3-(4′,6′-二取代均三氮苯-2′-基)-1,3,2-二氮磷杂环戊烷的合成及结构分析 1-取代苯磺酰基-3-(4′,6′-二取代均三氮苯-2′-基)-1,3,2-二氮磷杂环戊烷的合成及结构分析
Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences Pub Date : 1988-10-10 DOI: 10.1360/ZB1988-18-10-1037
陈茹玉, 刘准, 李晨曦, 刘小兰, 缪方明
{"title":"1-取代苯磺酰基-3-(4′,6′-二取代均三氮苯-2′-基)-1,3,2-二氮磷杂环戊烷的合成及结构分析","authors":"陈茹玉, 刘准, 李晨曦, 刘小兰, 缪方明","doi":"10.1360/ZB1988-18-10-1037","DOIUrl":"https://doi.org/10.1360/ZB1988-18-10-1037","url":null,"abstract":"本文研究了N-取代苯磺酰-N′-(4,6-二取代均三氮苯-2-)乙二胺与三(二烷胺基)膦的反应,发现了可一步得到关环的产物。从~1HNMR,~(13)CNMR谱观察到在室温下均三氮苯环的单键旋转阻滞现象,X衍射结果对此作了进一步讨论。磷杂环最稳定的构象为袋式,从键长以及环外氮原子杂化状态推测这类化合物在磷与环外氮原子之间有一定程度的dπ-pπ键。","PeriodicalId":223601,"journal":{"name":"Science in China Series B-Chemistry, Biological, Agricultural, Medical & Earth Sciences","volume":"206 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132712300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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