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Differential measurement of atmospheric refraction using a telescope with double fields of view

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Research in Astronomy and Astrophysics 2015年第10期15卷 1742-1750页

作者： yong Yu jian-Jun Cao zheng-Hong Tang Hao Luo Ming Zhao Shanghai Astronomical Observatory Chinese Academy of Sciences University of Chinese Academy of Sciences

For the sake of advancing theoretical research about atmospheric refrac- tion, the atmospheric refraction observed at lower angles of elevation is still worth analyzing and exploring. In some engineering applications, objects with a larger zenith distance must sometimes be observed. Carrying out observational research on atmospheric refraction at lower angles of elevation has an important significance. However, it has been considered difficult to measure the atmospheric refraction at lower angles of elevation. A new idea for determining atmospheric refraction by utilizing differential measurement with double fields of view is proposed. Taking the observational principle used by the HIPPARCOS satellite as a reference, a prototype with double fields of view was developed. In August 201 3, experimental observations were carried out and atmospheric refractions at lower angles of elevation were obtained by the prototype. The measured value of atmospheric refraction at a zenith distance of 78.8° was 240.23″±0.27″, and the feasibility of differential measurement of atmospheric refraction with double fields of view was verified. Limitations of the prototype, such as inadequate ability to gather light, lack of accurate meteorological data recording, and a low level of automation in observation and data processing, are pointed out, which need to be improved in subsequent work.

关键词： astrometry -- atmospheric effects -- methods: observational

Low-power clock-less hardware implementation of the rijndael S-box for wireless sensor networks

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The Journal of China Universities of Posts and Telecommunications 2007年第4期14卷 104-109页

作者： ZENG yong-hong ZOU Xue-cheng LIU zheng-lin LEI jian-ming Research Center for VLSI and Systems Department of Electronic Scienceand Technology Huazhong University of Science and TechnologyWuhan 430074 China

The recent development of microelectronics techniques and advances in wireless communications have made it feasible to design low-cost, low-power, multifunctional and intelligent sensor nodes for wireless sensor networks （WSN）. The design challenges for an efficient WSN mainly lie in two issues： power and security. The Rijindael algorithm is a candidate algorithm for encrypting data in WSN. The SubByte （S-box） transformation is the main building block of the Rijindael algorithm. It dominates the hardware complexity and power consumption of the Rijindael cryptographic engine. This article proposes a clock-less hardware implementation of the S-box. In this S-box, l） The composite field arithmetic in GF（（2^4））2 was used to implement the compact datapath circuit; 2） A high-efficiency latch controller was attained by utilizing the four-phase micropipeline. The presented hardware circuit is an application specific integrated circuit （ASIC） on 0.25 μm complementary mental oxide semiconductor （CMOS） process using three metal layers. The layout simulation results show that the proposed S-box offers low-power consumption and high speed with moderate area penalty. This study also proves that the clock-less design methodology can implement high- performance cryptographic intellectual property （IP） core for the wireless sensor node chips.

关键词： WSN rijindael algorithm S-box clock-less composite field arithmetic four-phase micropipeline

Screening and performance of L-14, a novel, highly efficient and low temperature-resistant cellulose-degrading strain

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International Journal of Agricultural and Biological Engineering 2020年第1期13卷 247-254页

作者： Guoxiang zheng Zhaoxin Lu jian Li Shuang Ai yong Sun College of Engineering Northeast Agricultural UniversityHarbin 150030China Key Laboratory of Pig-breeding Facilities Engineering Ministry of Agriculture and Rural AffairsHarbin 150030China Heilongjiang Key Laboratory of Technology and Equipment for the Utilization of Agricultural Renewable Resources Harbin 150030China

In view of the low bioconversion efficiency of agricultural biomass waste in low-temperature environments in winter,a low-temperature-resistant cellulose-degrading strain,L-14,was successfully screened by restrictive cultures from humus-rich soil in the Daqing Zhalong wetland *** to morphological observations and 18S rDNA sequence analysis,the cellulose-degrading strain L-14 was identified as a Neurospora sp,belonging to *** parameters,such as temperature,initial pH,carbon,nitrogen and lecithin,were optimized using a single-factor experiment and a response surface methodology(RSM).When the temperature was 16°C,the optimal conditions for enzyme production were an initial pH 8.20,10.45 g/L of bran,5.28 g/L of yeast powder,and 4.25 g/L of *** carboxymethyl cellulase(CMCase)activity of strain L-14 was 63.598 IU/*** L-14 had a high level of cellulose degradation activity,excellent resistance to low temperatures and environmental adaptability,indicating its good application prospects in substrates pretreatment of biogas engineering.

关键词： low-temperature-resistant Neurospora sp. 18S rDNA sequence carboxymethyl cellulase response surface methodology

Parameter estimation for rigid body after micro-Doppler removal based on L-statistics in the radar analysis

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Journal of Systems Engineering and Electronics 2015年第3期26卷 457-467页

作者： yong Wang jian Kang School of Electronics and Information Engineering Harbin Institute of Technology

In traditional inverse synthetic aperture radar （ISAR） imaging of moving targets with rotational parts, the micro-Doppler （m-D） effects caused by the rotational parts influence the quality of the radar images. Recently, L. Stankovic proposed an m-D removal method based on L-statistics, which has been proved effective and simple. The algorithm can extract the m-D effects according to different behaviors of signals induced by rotational parts and rigid bodies in time-frequency （T-F） domain. However, by removing m-D effects, some useful short time Fourier transform （STFT） samples of rigid bodies are also extracted, which induces the side lobe problem of rigid bodies. A parameter estimation method for rigid bodies after m-D removal is proposed, which can accurately re- cover rigid bodies and avoid the side lobe problem by only using m-D removal. Simulations are given to validate the effectiveness of the proposed method.

关键词： parameter estimation L-statistics micro-Doppler (m-D) radar imaging.

Earthquake potential of the seismic gap between the Wenchuan and Lushan earthquakes:Current status,thoughts,and challenges

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Science China Earth Sciences 2021年第3期64卷 503-506页

作者： yong zheng Rumeng GUO State Key Laboratory of Geological Processes and Mineral Resources Institute of Geophysics and GeomaticsChina University of Geosciences(Wuhan)Wuhan430074China Earth System Science Programme The Chinese University of Hong KongHong Kong999077China Institute of Precision Measurement Science and Technology Innovation Chinese Academy of SciencesWuhan430071China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing100049China

*** on the seismic gap between the Wenchuan and the Lushan earthquakes The 2008 Mw7.9 Wenchuan earthquake and the 2013 Mw6.9 Lushan earthquake,which occurred in the Longmenshan fault system(hereafter called LMSFS),cau... 详细信息

关键词： seismic earthquake fault

Design, Synthesis and Biological Activity of Substituted-N-[4-(substituted-phenylsulfamoyl)phenyl]benzamide as Potential AHAS Inhibitors

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Chinese Chemical Letters 2006年第12期17卷 1555-1558页

作者： jian Guo WANC yong Jun XIAO yong Hong LI Xing Hai LIU zheng Ming LI State-Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071

Based on the crystal structure of AHAS/sulfonylurea complex, we obtained 296 compounds with low binding energy towards AHAS via virtual screening. One series of them have been synthesized. Preliminary bioassay indicated that some compounds displayed good herbicidal activity on rape and bamygrass and inhibited AHAS to some extent. This study indicated the rationality of our molecular design based on the crystal structure of target enzyme.

关键词： AHAS molecular docking organic synthesis biological activity

Synergistic reaction behavior of pyrolysis and reduction of briquette prepared by weakly caking coal and metallurgical dust

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Journal of Iron and Steel Research International 2023年第7期30卷 1367-1380页

作者： zheng-jian Liu Ming-hui Cao jian-liang Zhang Run-sheng Xu Yao-zu Wang Ji-yong Yu Yu-chen Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

Co-carbonization of weakly caking coal and zinc-containing dust to prepare highly reactive ferro-coke and collaboratively recover zinc powder is one of the feasible ways for steel enterprises to recycle zinc-containing *** pyrolysis mass loss behavior of adding blast furnace dust with different zinc contents to different ferro-coke materials was systematically studied by thermogravimetry and differential thermogravimetry analysis,and the kinetic mechanism of pyrolysis-reduction reaction of hybrid briquette was *** results of thermogravimetric curve analysis show that the addition of zinc oxide to the sample has no significant effect on the mass loss rate of the sample below 580℃,and the pyrolysis mass loss of zinc oxide mainly occurs between 800 and 1000℃.Kinetic analysis results show that the pyrolysis of zinc-containing samples is controlled by chemical reactions below 580℃.The reaction at 580–700℃ is controlled by the nucleation and growth model,and that above 700℃ is mainly controlled by *** results of X-ray diffraction analysis show that the pyrolysis process can effectively remove zinc oxide from ferro-coke.

关键词： Zinc-containing dust Weakly caking coal Ferro-coke Pyrolysis Reduction Thermal reaction analysis Kinetic analysis

Suppression of human colon tumor growth by adenoviral vector-mediated NK4 expression in an athymic mouse model

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World Journal of Gastroenterology 2007年第13期13卷 1938-1946页

作者： jian-zheng Jie State Key Laboratory ofMolecular Virology and Genetic Engineering Beijing 100730China Natinoal Institute for Viral Disease Control and Prevention ChinaCDC Beijing 100052 China Department of General Surgery China-JapanFriendship Hospital Beijing 100029 China

AIM： To investigate the suppressive effects of adenoviral vector-mediated expression of NK4, an antagonist of hepatocyte growth factor （HGF）, on human colon cancer in an athymic mouse model to explore the possibility of applying NK4 to cancer gene therapy. METHODS： A human colon tumor model was developed by subcutaneous implantation of tumor tissue formed by LS174T cells grown in athymic mice. Fifteen tumorbearing mice were randomized into three groups （n= 5 in each group） at d 3 after tumor implantation and mice were injected intratumorally with phosphate-buffered saline （PBS） or with recombinant adenovirus expressing 13-galactosidase （Ad-LacZ） or NK4 （rvAdCMV/NK4） at a 6-d interval for total 5 injections in each mouse. Tumor sizes were measured during treatment to draw a tumor growth curve. At d 26 after the first treatment, all animals were sacrificed and the tumors were removed to immunohistochemically examine proliferating cell nuclear antigen （PCNA）, microvessel density （represented by CD31）, and apoptotic cells. In a separate experiment, 15 additional athymic mice were employed to develop a tumor metastasis model by intraperitoneal injection （ip） of LS174T cells. These mice were randomized into 3 groups （n = 5 in each group） at d 1 after injection and were treated by ip injection of PBS, or Ad-LacZ, or rvAdCMV/NK4 at a 6-d interval for total two injections in each mouse. All animals were sacrificed at d 14 and the numbers and weights of disseminated tumors within the abdominal cavity were measured. RESULTS： Growth of significantly suppressed human colon tumors were in the athymic mice treatedwith rvAdCMV/NK4 （2537.4± 892.3 mm^3） compared to those treated by either PBS （5175.2 ± 1228.6 mm^3） or Ad-LacZ （5578.8± 1955.7 mm^3）（P 〈 0.05）. The tumor growth inhibition rate was as high as 51%. Immunohistochemical staining revealed a similar PCNA labeling index （75.1% ± 11.2% in PBS group vs 72.8% ± 7.6% in Ad-LacZ group vs 69.3% ± 9.4% in rvAdCMV/ NK4 group） in all

关键词： Human colon cancer NK4 Hepatocytegrowth factor Adenoviral vector Gene therapy

Reaction behaviors occurring in Ti/Al foil metallurgy

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Rare Metals 2016年第1期35卷 100-105页

作者： zheng-Zhang Shen Jun-Pin Lin yong-Feng Liang Lai-Qi Zhang Guo-jian Hao State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

Reaction behaviors occurring in Ti/Al foil metallurgy were systematically *** emphasis was focused on the reaction between solid Al and Ti as well as subsequent reaction between TiAland Ti *** the solid reaction between Al and Ti,the presence of residual Al is mainly caused by inhomogeneous growth of TiAllayer and micro-voids existing at the ***,through reaction between molten Al and Ti,TiAl/Ti multilayer can be achieved with complete consumption of *** subsequent high-temperature heat treatment,TiAl/Ti multilayer will eventually turn into TiAl/TiAl multilayer accompanying with simultaneous formation and successive disappearance of intermediate phases,such as TiAland ***,it is found that the growth direction of TiAl layer changes as a function of annealing time between different couples in multi-intermetallics system.

关键词： Reaction behavior Foil metallurgy Multilayer TiAl3 TiAl