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A sensitive xanthine oxidase electrode with silk net for estimating fish freshness

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Chinese Journal of Chemistry 1996年第5期14卷 404-411页

作者： Peng, TZ Yang, LJ Shen, lq HANGZHOU UNIV DEPT CHEMHANGZHOU 310028ZHEJIANGPEOPLES R CHINA HANGZHOU INST COMMERCE DEPT FOOD SCIHANGZHOU 310035PEOPLES R CHINA

An enzyme biosensor was constructed using a plate platinum electrode and immobilized xanthine oxidase (XOD). Only a very small quantity of enzyme was chemically immobilized on a special silk net. Hydrogen peroxide released during the enzymatic reaction was detected by the electrode at +0.65 V (vs. Ag/AgCl). The electrode was very sensitive to hypoxanthine and its detection limit was 1X10(-7) mol/L. When it was applied to the determination of fish freshness, the results agreed well with those obtained by traditional methods-determination of total volatile basic nitrogen (TVB-N) and microbial count. A range for estimating the freshness of river fish was suggested.

关键词： xanthine oxidase electrode biosensor amperometry fish freshness

Diterpenoid Alkaloids from Aconitum Pendulum

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Chinese Chemical Letters 1997年第11期8卷 967-970页

作者： Zhang, SM Tan, lq Ou, QY Chinese Acad Sci Lanzhou Inst Chem Phys Lanzhou 730000 Peoples R China

A new diterpenoid 12-epiacetyldehydrolucidusculline (1) and a new norditerpenoid alkaloid 2-hydroxydeoxyaconitine (2) were isolated from the roots of Aconitum pendulum, together with eight known alkaloids aconitine (3), deoxyaconitine (4), 3-acetylaconitine (5), 12-epiacetyldehydronapelline (6), dehydrolucidusculline (7), dehydronapelline (8). 12-epidehydronapelline (9), and noeline (10). The structures of the new alkaloids (1-2) were determined on the basis of spectral method.

关键词： Wang chen Diterpenoid Alkaloids from Aconitum Pendulum

Effect of mating status on the fecundity of a cricket, Teleogryllus emma

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Insect Science 2011年第3期18卷 320-324页

作者： lq-Quan Zhao Dao-Hong Zhu College of Forestry Central South University of Forestry & Technology Central South University of Forestry & Technology Changshe China Hunan First Normal University Central South University of Forestry & Technology Changshe China College of Life Science and Technology Central South University of Forestry & Technology Changshe China

Fecundity in some insects is affected by mating status. The effect of mating status on the fecundity and total egg production of Teleogryllus emma （Ohmachi et Matsumura）（Orthoptera： Gryllidae） was examined in this study. The results showed that the pre-oviposition period was shorter for amphigonic females than that for virgin females. However, no significant difference in pre-oviposition was found between amphigonic females and those that had mated with a male with either the phallodeum or testes extirpated. There is no difference in adult longevity between the above four groups. The fecundity and total egg production were much higher in amphigonic females than in those controlled under the three non-amphigonic treatments. The females of T. emma that mated with the testes-extirpated males produced more eggs （up to two-fold more） than both the virgin females and those that mated with the phallodeum-extirpated males, but there was no difference between them. The fecundity-enhancing substances transferred from male to female can stimulate the female to produce more eggs, but this stimulation has to occur in collaboration with sperm.

关键词： fecundity mating status pre-oviposition Teleogryllus emma total egg production

Grayanane Diterpenoids from Pieris formosa

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Chinese Chemical Letters 1998年第5期9卷 465-467页

作者： Wang, lq Ding, BY Zhao, WM Qin, GW Chinese Acad Sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China Hangzhou Univ Coll Life Sci Hangzhou 310012 Peoples R China

Three grayanane diterpenoids 1-3 were isolated from Pieris formosa. 1 was identified as a new natural product and 2 and 3 as known grayanoside C and grayanotoxin XVIII on the basis of spectral analysis.

关键词： Pieris formosa grayanane diterpenoid pierisformosin A

On the electron-beam (EB) irradiation and grafting of acrylic monomers onto EVA copolymers

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Chinese Science Bulletin 1997年第18期42卷 1549-1554页

作者： Zhang, S Wang, JQ Xie, lq Wen, CL BEIJING INST TECHNOL SCH CHEM ENGN & MAT SCISTATE KEY LAB FLAME RETARDANT MATBEIJING 100081PEOPLES R CHINA

IN an ordinary way the grafting induced by electron and gamma preirradiations widely used for improving the compatibility of polymers in composites gives rise to an enhancement of their mechanical properties. However, very few have been reported in the flame retardancy of polymers using these sorts of techniques. Wilkie investigated the flame retardancy of photo-initiation grafted polymers. An attempt is made in this paper to try to use the EB preirradiation on EVA copolymers with different VA contents and the subsequent grafting with saponification under atmosphere and to expedite the charring of polymers upon heating. Characterization of the flammability of the preirradiated EVA copolymers grafted with acrylic monomers indicates that this approach turns out to be a promising way and worthy of doing.

关键词： electron-beam irradiation grafting flame retardancy EVA copolymers.

Spatiotemporal modes of global sea surface temperature variability

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Science China Earth Sciences 2017年第3期60卷 508-516页

作者： ZHANG XiangMing chen chen LIAN Tao chen DaKe State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyHangzhou 310012China Lamont-Doherty Earth Observatory of Columbia University New York 10027USA

This study identifies the salient global modes of sea surface temperature variability based on 145 years of HadlSST *** the traditional mode identification by EOF analysis,a combination of wavelet and EOF analysis is used to extract the leading modes at distinct time *** spatial patterns of some well-known regional modes are recovered,with the global connection and frequency content of these modes being *** analysis indicates that,in terms of global influence,the Pacific Ocean is the major player,and the tropical Pacific is the center of action on various time *** Atlantic Ocean has its own outstanding modes,but their global impacts are not as strong as those from the *** Indian Ocean generally shows a passive response to the Pacific,with a basin-wide pattern in the *** some preliminary theoretical attempts,how to elucidate the dynamics underlying the global modes of sea surface temperature variability is still an open question.

关键词： Global mode Wavelet EOF

An easy model for prediction of human renal clear cell carcinoma：curve fitting for three kidney tumors observed for over 10 years

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Chinese Medical Journal 2014年第4期127卷 782-783页

作者： Yao L Li XS Zhang L He ZS Zhou lq Department of Urology Peking University First Hospital Beijing 100034 China Institute of Urology Peking University National Urological Cancer Center Beijing 100034 China

The current researches on natural history of small renal masses show that small renal tumors grow slowly,and few metastasize.1-4 As the length of follow-up is short in these studies （the longest mean follow-up time is 48 months）,changes in tumor size in vivo cannot be observed *** addition,the growth model of tumor is linear,and the average growth rate is used to reflect tumor growth in these ***,most malignant tumor growth curves were not *** may not be correct to assess the growth of tumors by linear models.

关键词： prediction model renal clear cell carcinoma

Long-term Energy Demand and CO_2 Problem in the PRC

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Journal of Systems Engineering and Electronics 1991年第1期2卷 29-41页

作者： lq YingzhongInst. for Techno-Economics and Energy System Analysis. P.O. Box 1021, Beijing 102201, China Inst. for Techno-Economics and Energy System Analysis. P.O. Box 1021 Beijing 102201 China

The long-term energy demand in China and the-Chinese share in global CO2 emission are forecasted on the basis of scenarios of population growth and economy development up to 2050 proposed in view of the interaction of energy, economy, environment and social development. The total energy demand in 2050 will reach 4.4~ 5.4 billion tce. It is shown in energy supply analysis that coal is China’s major energy in primary energy supply. The share of CO2 emission in the future Chinese energy system will be out of proportion to its energy consumption share because of the high persentage of coal to be consumed. It will reach about 27%. The nuclear option which would replace 30.7% of coal in the total primary energy supply will reduce the share by 9.8%. So the policy considerations on the future Chinese energy system is of great importance to the global CO2 issues.

关键词： Long-term forecast Energy demand CO2emission Climate change.

Photoinduced Weyl semimetal phase and anomalous Hall effect in a three-dimensional topological insulator

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Chinese Physics B 2021年第11期30卷 94-101页

作者： Meng-Nan chen Wen-Chao chen School of Science Hangzhou Dianzi UniversityHangzhou 310018China Institute of Advanced Magnetic Materials College of Materials and Environmental EngineeringHangzhou Dianzi UniversityHangzhou 310018China

Motivated by the fact that Weyl fermions can emerge in a three-dimensional topological insulator on breaking either time-reversal or inversion symmetries,we propose that a topological quantum phase transition to a Weyl semimetal phase occurs under the off-resonant circularly polarized light,in a three-dimensional topological insulator,when the intensity of the incident light exceeds a critical *** circularly polarized light effectively generates a Zeeman exchange field and a renormalized Dirac mass,which are highly *** phase transition can be exactly characterized by the first Chern number.A tunable anomalous Hall conductivity emerges,which is fully determined by the location of the Weyl nodes in momentum space,even in the doping *** predictions are experimentally realizable through pump-probe angle-resolved photoemission spectroscopy and raise a new way for realizing Weyl semimetals and quantum anomalous Hall effects.

关键词： Floquet theory Weyl semimetal topological phase transition Hall conductivity