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Digital coincidence acquisition applied to portable β liquid scintillation counting device

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Nuclear Science and Techniques 2013年第3期24卷 45-49页

作者： REN Zhongguo HU Bitao zhao zhiping LI Dongcang School of Nuclear Science and Technology Lanzhou University China Academy of Engineering Physics

A digital coincidence acquisition system applied to a portable liquid scintillation counting device is developed. The system which simplifies the device design consists of a digitizer card of Agilent U1066A DC438, a discriminator and a host computer. The anode analog pulses from two photomultiplier tubes are captured by the system, which adopts the sequence acquisition storage mode. By choosing proper threshold for each channel, coincidence time window of ±30 ns, and comparing the pulse amplitudes from two channels, the portable scintillation counting device can be used to detect β particles. For the unquenched standard 3 H sample, the results show that the detection efficiency is (58.5±0.1)% and the background is (86.7±0.7) cpm. Meanwhile, 3 H β spectrum is obtained.

关键词：计数装置液体闪烁便携式采集系统收购应用脉冲幅度检测效率

Climate changes in East China since the Late-glacial inferred from high-resolution mountain peat humification records

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Science China Earth Sciences 2009年第1期52卷 118-131页

作者： MA ChunMei ZHU Cheng ZHENG ChaoGui YIN Qian zhao zhiping School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210093China Department of Land Information Engineering Chuzhou CollegeChuzhou 239012China Nanjing Institute of Geography&Limnology Chinese Academy of SciencesNanjing 210008China

High-resolution peat humification records were obtained from Dajiuhu of the Shennongjia Mountains and Qianmutian of the Tianmu Mountains to study climate changes in East *** analyses of pollen,organic matters,TOC,and Rb/Sr indicate a high degree of peat humification and thus strong decomposition of organic matter when climate was ***,when climate was humid,the degree of humification is low because peat was preserved in a waterlogged *** humification from Dajiuhu occurred not only during the Younger Dryas(about 11.4-12.6 cal ka BP),the Blling-Allerd Warm Period(12.6-15.2 cal ka BP),and the Oldest Dryas(about 15.2-16.0 cal ka BP),but also during the early Holocene(about 11.4-9.4 cal ka BP),the 8.2 cal ka BP cold event,and the Holocene Optimum(about 7.0-4.2 cal ka BP).Both peat humification records since nearly 5 ka BP are consistent,showing that mountain peatland has synchronous responses to the East Asia monsoon-induced *** LOI data confirm the above *** monsoon precipitation since nearly 5 ka BP recorded in these two peat profiles can be divided into three *** 4.9-3.5 ka BP,precipitation amount was high but fluctuated *** 3.5-0.9 ka BP,precipitation amount was *** 0.9-0 ka BP,degree of humification reduced gradually,indicating the increase of monsoon *** to other high-resolution records from East China monsoon region shows that the monsoon precipitation records of the two peat profiles since nearly 16 ka BP are controlled by a common forcing mechanism of summer solar radicalization in the Northern Hemisphere.

关键词： mountain peat the Late-glacial the Holocene degree of humificatiom Dajiuhu of Shennongjia Mountains Qianmutian of Tianmu Mountains climate changes

Augmentation of tribenuron methyl removal from polluted soil with Bacillus *** BS2 and indigenous earthworms

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Journal of Environmental Sciences 2012年第8期24卷 1492-1497页

作者： Qiang Tang zhiping zhao Yajun Liu Nanxi Wang Baojun Wang Yanan Wang Ningyi Zhou Shuangjiang Liu State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China College of Life Science University of Science and TechnologyHefei 230026China Key Laboratory of Microbial Engineering at the Institute of Biology Henan Academy of SciencesZhengzhou 450008China Key Laboratory of Agricultural and Environmental Microbiology Wuhan Institute of VirologyChinese Academy of Sciences44 Xiao-Hong-ShanWuhan 430071China

Tribenuron methyl （TBM） is a member of the sulfonylurea herbicide family and is widely used worldwide. In this study, TBM- degrading bacteria were enriched with TBM as potential carbon, nitrogen or sulfur source, and 44 bacterial isolates were obtained. These isolates were phylogenetically diverse, and were grouped into 25 operational taxonomic units and 14 currently known genera. Three representatives, Bacillus sp. strain BS2, Microbacterium sp. strain BS3, and Cellulosimicrobium sp. strain BSI 1, were selected, and their growth and TBM removal from culture broth were investigated. In addition, indigenous earthworms were collected and applied to augment TBM degradation in lab-scale soil column experiments. Results demonstrated that Bacillus sp. strain BS2 and earthworms significantly increased TBM removal during soil column experiments.

关键词： biodegradation of tribenuron methyl Bacillus Microbacterium Cellulosimicrobium earthworm

Effect of Different Loadings on the Performance of Ni2P/Al2O3 Catalysts for Low-Temperature Thioethering and Selective Hydrogenation of Diolefins in Liquefied Petroleum Gas

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China Petroleum Processing & Petrochemical Technology 2023年第1期25卷 79-90页

作者： Xiao Han Sun Jinru Song Guoliang Xie Xianna Ke Ming Tong Yanbing zhao zhiping Wang Zijian Li Jiahan CNOOC CenerTech Tianjin Chemical Research and Design Institute Co LtdTianjin 300131China State Key Laboratory of Heavy Oil Processing and Beijing Key Lab of Oil&Gas Pollution Control China University of PetroleumBeijing 102249China

In this study,different loadings of x%Ni_(2)P/γ-Al_(2)O_(3)(x=6%,9%,12%,15%,18%)catalysts with aluminum oxide(Al_(2)O_(3))as the carrier,nickel chloride(NiCl2)as the nickel(Ni)source,and ammonium hypophosphite(NH_(4)H_(2)PO_(2))as the phosphorus(P)source were prepared by the equal volume impregnation method to investigate the effects of different loadings on the performance of the selective hydrogenation of diolefins and thiol etherification in *** physicochemical properties of the catalysts were characterized by XRD,BET,SEM,TEM,H_(2)-TPR,and XPS,and the catalytic activity of the catalysts was evaluated in a fixed-bed *** results showed that a change in the loading affected the catalyst crystalline phase structure and size,specific surface area,P coverage,active phase dispersion,and catalytic *** 6%,9%,and 12%loadings the catalysts had an Ni phase but there was no obvious Ni_(2)P phase in the nickel phosphide;at 15%loading a single Ni_(2)P phase was obtained,and at 18%loading both Ni_(2)P and Ni1_(2)P_(5) phases *** was a P enrichment on the catalyst surface,and the higher the loading the more P species were enriched on the surface,but some of the P was lost during the catalyst reduction process due to the production of phosphine(PH3)*** 15%Ni_(2)P/γ-Al_(2)O_(3) catalyst had the largest Ni/Al ratio and the best *** Ni_(2)P active phase size was small at about 4.25 nm and Ni_(2)P was uniformly dispersed on the catalyst surface without *** 15%Ni_(2)P/γ-Al_(2)O_(3) catalyst had the best catalytic activity at a pressure of 2.0 MPa,a liquid hourly space velocity(LHSV)of 3.0 h-1,and a hydrogen to hydrocarbon ratio of *** 1,3-butadiene conversion was 97.45%and the methanethiol removal was 100%at a temperature of 140℃.

关键词： Ni_(2)P dispersion low-temperature thioethering selective hydrogenation of diolefins

High-resolution geochemistry records of climate changes since late-glacial from Dajiuhu peat in Shennongjia Mountains,Central China

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Chinese Science Bulletin 2008年第S1期53卷 28-41页

作者： MA ChunMei ZHU Cheng ZHENG ChaoGui WU ChunLin GUAN Yong zhao zhiping HUANG LinYan HUANG Run School of Geographic and Oceanographic Sciences of Nanjing University Nanjing 210093China Department of Geography Chuzhou CollegeChuzhou 239012China

A peat core with depths of 297 cm was obtained from the Dajiuhu Basin(31°29′27″N,109°59′45″E,1760 m)in Hubei Province,Central China.10 AMS ages provide a time control and reveal that this core spans the past about 16.0 kaBP(calibrated age)(1 4C age:13.3 kaBP).Multi-proxy indexes analysis of geochemistry shows the following character of climate and environmental changes since about 16 kaBP:(1) The climate during the late-glacial period was cold and wet as a whole,but fluctuated continually.11.4- 12.6 ***,12.6-15.2 *** and 15.2-16 kaBP were corresponding respectively to the Younger Drays,Bφlling-Allerφd Warm Period and the Oldest Drays.(2)Inheriting the some climate characteristics of the late-glacial,the climate during the early-Holocene was wet and temperature increased gradually,during which an obvious dry event around 10.6 *** appeared.(3)The climate during the mid-Holocene was genarally warm and *** 9.2-7.5 kaBP,temperature increased gradually, precipitation was less comparatively and the 8.2 kaBP cold event which might be representative in the globe was reflected ***,multi-proxy records were relatively stable during 6.7-4.2 kaBP, which shows the best water and thermal condition in the Holocene Optimum.(4)Around 4.2 kaBP,the climate and environment transform from warm and wet to cool and dry,which may result in the collapse of the Neolithic Culture and midwifery the civilization of Xia Dynasty in this *** 0.9 kaBP,the climate turned cool and *** and environmental changes archived in Dajiuhu peat respond to the global changes since the late-glacial period and can be contrasted to the changes recorded in other high-resolution archives from the East Asia Monsoon region,which take on the variety model that the monsoon strengthened abruptly after the late-glacial,was strong during the early Holocene,subse- quently declined and became weak after the middle Holocene with dry *** to our analysis,the driving me

关键词： late-glacial Holocene Dajiuhu of Shenongjia peat climate changes geochemistry

Advances in the Coenzyme Q10 Biosynthesis Pathway in Rhodobacter sphaeroides and the Enhancement of Coenzyme Q10 Production Based on Metabolic Engineering

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Agricultural Biotechnology 2019年第4期8卷 1-6,13页

作者： Kuo TANG zhiping zhao School of Chemical Engineering Sichuan University of Science & Engineering

Coenzyme Q10 is widely used in food,cosmetics and pharmaceuticals,possessing a broad *** sphaeroides is enriched in natural coenzyme Q10 and is becoming an important microorganism for producing natural coenzyme *** paper reviewed the biosynthesis pathways of coenzyme Q10 in *** and the advances in enhancement of coenzyme Q10 production in *** based on metabolic engineering.

关键词： Rhodobacter sphaeroides Coenzyme Q10 Biosynthesis Metabolic engineering

Analysis on the Stability of Dendrobium Polysaccharides in Simulated Beverages

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Agricultural Biotechnology 2015年第4期4卷 70-71,76页

作者： Jing YUAN Li ZHANG zhiping zhao School of Chemistry and Pharmaceutical Engineering Sichuan University of Science & Engineering

[ Objective ] This study aimed to investigate the stability of Dendrobium polysaccharides in simulated beverages, thus providing theoretical basis for further development of Dendrobium beverages. [ Method] The prepared simulated Dendrobium juice beverages and extracted Dendrobium polysaccharides were added into wine and Chinese liquor and treated under different pH, temperature and light conditions to determine changes in Dendrobium polysaccharide content. [ Result] Dendrobium polysaccharides exhibited high stability in beverages under neutral pH, room temperature, dark conditions. [ Conclusion] Dendrobium polysaccharides can be used for the development of Dendrobium beverages.

关键词： Dendrobium polysaccharides Beverages Stability

Power Network Lightning Accident Quick Inquiry with the Lightning Location System

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Geo-Spatial Information Science 2008年第1期11卷 43-48页

作者： NIE zhiping zhao Wenguang ZHANG Ping WEN Yinping CHEN Weijiang Hubei Key Laboratory of Control Structure HUST 1037 Luoyu Road Wuhan 430074 China

At present, lightning is one of the 10 natural disasters, and it is also the top environmental factor of power interruption. It often causes huge losses to the electric system. The Wuhan High Voltage Institute of the State Grid Corporation of China and Huazhong University of Science and Technology have been researching and developing lightning location systems （LLSs） since the late 1980s. In the mid-1990s, a lightning detection network was created in 29 provinces and cities in China. It is primarily applied to rapidly find lightning accidents, which greatly reduces power interruption. Also, it ensures high efficiency and safe operation of the electricity system. Remarkable benefit is achieved. China＇s LLS went through an ＂orientation positioning - time difference positioning - integrated positioning＂ development process. The positioning precision, detection efficiency, degree of automation, practicability and applied range are improved. Also, a lightning information system plan of the national network has been implemented, which services the whole society.

关键词： lightning location power network lightning accident accident inquiry lightning information system

Speech emotion recognition based on statistical pitch model

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Chinese Journal of Acoustics 2006年第1期25卷 87-96页

作者： WANG zhiping zhao Li ZOU Cairong Department of Radio Engineering Southeast University Nanjing 210096

A modified Parzen-window method, which keep high resolution in low frequencies and keep smoothness in high frequencies, is proposed to obtain statistical model. Then, a gender classification method utilizing the statistical model is proposed, which have a 98% accuracy of gender classification while long sentence is dealt with. By separation the male voice and female voice, the mean and standard deviation of speech training samples with different emotion are used to create the corresponding emotion models. Then the Bhattacharyya distance between the test sample and statistical models of pitch, are utilized for emotion recognition in speech. The normalization of pitch for the male voice and female voice are also considered, in order to illustrate them into a uniform space. Finally, the speech emotion recognition experiment based on K Nearest Neighbor shows that, the correct rate of 81% is achieved, where it is only 73.85% if the traditional parameters are utilized.

关键词： emotion recognition statistical models classification method standard deviation high frequencies low frequencies high resolution uniform space test sample