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Chemical Research in Chinese universities 1995年第3期11卷 206-214页

作者： Tang, Zong-xun Zhang, Feng-xing Guo, Zhi-zhen Huang, Jing-ying Hao, Zhi-feng nw univ xian DEPT CHEMXIAN 710069PEOPLES R CHINA

he solubilities , refractive indexes of saturated solutions of the quaternary re-ciprocal system Li￣+ , Br￣(-) ,I￣(-)H_(2)O and its boundary ternary system NH_(4)Br-NH_(4)I-H_(2)O at 25℃ have been investigated using isothermal method. In the titleternary system which belongs to Roozeboom Ⅳ type, there are two limited solid so-lutions. Entering into the quaternary system, the region of the solid solutions re-duces and disappears with the increase of Li￣+ , and finally, the quaternary systembecomes a simple system.

关键词： Quaternary reciprocal system Lithium bromide Ammonium bromide,Lithium iodide Ammonium iodide.

The Reaction of Benzimidazole Methiodide Salt with Bis-Grignard Reagent

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Chinese Chemical Letters 1997年第6期8卷 465-466页

作者： Shi, Z Gu, H nw univ xian DEPT CHEMXIAN 710069PEOPLES R CHINA

The reaction of benzimidazole methoidide salt with bis-Grignard reagent is reported, and a new method for the preparation of dialdehyde is provided.

关键词： The Reaction of Benzimidazole Methiodide Salt with Bis-Grignard Reagent

A New Platy-armored Worm from the Early Cambrian Chengjiang Lagerstatte,South China

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Acta Geologica Sinica(English Edition) 2003年第1期77卷 1-6页

作者： HAN Jian, ZHANG Xingliang, ZHANG Zhifei and SHU Degan Early Life Institute and Department of Geology, Northwest university, Xi’an, Shaanxi 710069, nw univ xian Early Life Inst Xian 710069 Shaanxi Peoples R China nw univ xian Dept Geol Xian 710069 Shaanxi Peoples R China

The Lower Cambrian Chengjiang Lagerstatte provides a good window to explorethe origin and radiation of early bilaterians. Here we describe a netted sclerite-bearing wormTabelliscolex hexagonus gen. et sp. nov., and tentatively assign it to palaeoscolecidans ofpriapulids. The cuticle of the animal is covered with two kinds of platy sclerites which areconstructed by hexagonally arranged tubercles Similar structures of the sclerites can be seen onsome Cambrian palaeoscolecidans and lobopods, so, this new species is critical for understanding therelationships between lobopods and palaeoscolecidans.

关键词： Chengjiang Lagerstatte Cambrian Priapulida sclerites China

Polarographic Catalytic Wave of Lysozyme

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Chinese Chemical Letters 1998年第6期9卷 557-560页

作者： Gou, W Yang, YN Song, JF nw univ xian Inst Analyt Sci Xian 710069 Peoples R China

This paper reports a polarographic catalytic wave of lysozyme (LE) in the presence of KIO3. The mechanism of the catalytic wave was discussed. It is illustrated by the catalytic wave of LE that, besides the Brdicka cu... 详细信息

关键词： polarographic catalytic wave lysozyme protein KIO3

New　Polarographic　Immunoassay　Using　Copper　Ion　as　Catalyst　for　Conversion　of　Substrate　Instead　of　Natural　Enzyme

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Chinese Chemical Letters 1996年第10期7卷 922-923页

作者： Song, JF Wang, JX Guo, W Zhao, MR nw univ xian INST ELECTROANALYT CHEMXIAN 710069PEOPLES R CHINA

A new electrochemical immunoassay based on catalytic conversion of substrate by labeled metal ion and polarographic detection of generated product was developed. In this immunoassay,copper ion was used A catalyst for the conversion of substrate to substitute natural enzyme. Copper ion was labeled to antigens such as Human serum albumin(HSA), Diphtheria Toxoid (DT),Tetanus Toxoid (TT ) through bifunctional chelating agent diethylenetriamine pentaacetic acid (DTPA).After heterogeneous competitive immune reaction, the labeled copper ion was released by acidification, and then catalyzes chemically the conversion of substrate o-phenyldiamine (OPD ) to electroactive product 2,3-diaminophenazine (DAP). The product DAP was detected by using linearsweep polarography. The sensitivity of the proposed assay for the determination of HSA, DT and TT is superior to those of previous one based on direct detection of the labeled metal ion.

关键词： Conversion Catalyst

Pediculate Brachiopod Diandongia pista from the Lower Cambrian of South China

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Acta Geologica Sinica(English Edition) 2003年第3期77卷 288-293页

作者： ZHANG Zhifei, HAN Jian, ZHANG Xingliang, LIU Jianni and SHU DeganEarly Life Institute and Key Laboratory for Continental Dynamics of the Ministry of Education,Northwest university, Xi’an, Shaanxi 710069 E-mail: zhangelle@*** Wang Si’en and Xie Guanglian nw univ xian Early Life Inst Xian 710069 Peoples R China nw univ xian Key Lab Continental Dynam Minist Educ Xian 710069 Peoples R China

The Chengjiang Lagerstatte has been celebrated for prolific soft-bodied fossils. Based on specimens recently excavated in the Chengjiang Lagerstatte by the Early Life Institute, Northwest university, Diandongia pista Rong, 1974, is directly revealed to be a pediculate brachiopod, assigned to the Family Botsfordiidae, as is further confirmed by the exceptionally preserved vascular system including dorsal and ventral mantle canals. These specimens described herein exhibit some peculiarities, notably the extremely thin and long pedicles, which suggest that Diandongia is epifaunal rather than burrowing brachiopod. A study of this group of animals indicates that they may be vital to understand the relationship between the lingulids and the remaining brachiopods, and the character evolution of the early Cambrian brachiopods.

关键词： Chengjiang Lagerstatte soft-bodied fossils mantle canals character evolution Cambrian China

The evidence of Sm-Nd isochron age for the early Paleozoic ophiolite in Mangya area,Altun Mountains

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Chinese Science Bulletin 1998年第9期43卷 754-756页

作者： Liang Liu Zicheng Che Yan Wang Jinhai Luo Jianqi Wang Zhangjian Gao nw univ xian Dept Geol Xian 710069 Peoples R China

The REE patterns of the basic volcanic rocks in Mangya area, Altun, are slight rich in LREE with (La/Ya)-N=1.69-3.20, (La/Sm)-N=1.37-1.87, other trace element ratios of the rocks are Th/Ta≈1 (for a few samples greater than 1.5), Nb/Y=0.34-0.62, Ti/Y=310-443 (on the average: 381), Ti/V=37-62, Zr/Nb=9.4-12.4, Sr/Rb=12-80 (on the average: 37), and Nb/Th=7.7-16.8. These features are similar to that of E-MORE or OIB. The ε Nd(t) value, being 3.95- 4.12, shows that the source of the volcanic rocks is derived from depleted asthenosphere mantle mixed with materials from enriched mantle. These, together with the information of geological setting and rock assemblages, indicate that the basic volcanic rocks are of ophiolite. The Sm-Nd isotope ages for the eight basic volcanic rock samples construct a straight line with good correlation, and the calculated isochron age is (481.3±53) Ma. Besides, the eight calculated ε Nd(t) and model ages are close to each other, which suggests that they are homologous, so the isochron is not a mixed line. In the meantime, the isochron age ((481.3±53) Ma) is lower than the model ages (T DM=1 004-1 534 Ma) of the samples, suggeting that the isochron age represents the formation age of the basic volcanic rocks and the ophiolite belt in Mangya area, Altun is formed in the early Paleozoic (Cambrian-Ordovician). In spite of the greater uncertainty of the age, it is still reliable because it is consistent with the age constrained by the regional strata.

关键词： Altun mountains Mangya ophiolite Sm-Nd isochron age.

Biomimetic synthesis for precursor of muscone

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Chinese Science Bulletin 2001年第5期46卷 393-395页

作者： Zhen Shi Juli Qiang Zheng Li nw univ xian Dept Chem Xian 710069 Peoples R China

Muscone is a precious fragrant compound scarce in nature. Many attempts have been made to synthesize this unique natural product. In this work, the one-carbon unit transfer reaction of tetrahydrofolate coenzyme was initiated. Benzimidazolium salt was used as the tetrahydrofolate coenzyme model at formic acid oxidation level and di-Grignard reagent as the nucleophile to which one-carbon unit was transferred; the biomimetic synthesis of 2,15-hexade-canedione, a precursor of muscone, was successfully accomplished by using the addition-hydrolysis reaction of benzimidazolium salt with Grignard reagent. And an important useful method for the synthesis of muscone is provided.

关键词： muscone 2 15-hexadecanedione biomimetic synthesis.

A NOVEL SILACARBOCYANINE DYE

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Chinese Chemical Letters 1995年第1期6卷 17-18页

作者： Yao Jun ZHANG Ji xiang HAO Zu Xun ZHANG Department of Chemistry, Northwest university, Xi’an, 710069 nw univ xian Dept Chem Xian 710069 Peoples R China

A new type of photographic spectral sensitizer containing silicon-carbon double. bond is reported. The application tests show that the dye has excellent sensitivity in silver iodobromide emulsion and that the sensitivity maximum (S-max) of emulsion sensitized by the dye gives a hypsochromic shift about 70nm as compared with the absorption maximum (lambda (max)) of the dye in methanol. This phenomenon differs entirely from typical photographic spectral sensitizing dye.

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Magnetic characteristics and their paleoclimatic significance of Fengzhou loess in the Qinling Mountains of China

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Chinese Science Bulletin 1998年第18期43卷 1571-1575页

作者： xiangyi Lei Leping Yue Jianqi Wang Li Zhang nw univ xian Dept Geol Xian 710069 Peoples R China

The Fengzhou loess section is very typical in the Qinling Mountains. The section, about 82 m thick and underlain by the Neogene red clay, consists of 33 layers of loess and 33 layers of paleosol. The section covers Brunhes normal polarity zone and Matuyama reversed polarity zone, and the B/M boundary is located in the middle of L\-8. Matuyama reversed polarity zone records Jaramillo, Olduvai and Reunion normal polarity subchrons. The boundary between Matuyama reversed polarity zone and Gauss normal polarity zone (M/Ga) appears in the lithological boundary between loess and the Neogene red clay. Loess accumulation in Fengzhou started before 2.48 Ma. The magnetic susceptibility curve indicates 33 cold_dry and humid_warm cycles of paleoclimatic variation in the Qinling Mountains during the last 2.48 Ma. The above climatic fluctuation may be well compared with that of the oxygen isotopic records from deep_sea deposits.

关键词： Qinling Mountains paleoclimatic change magnetic susceptibility magnetostratigraphy of loess.