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A 20 μW 95 dB dynamic range 4th-order Delta-Sigma modulator with novel power efficient operational transconductance amplifier and resonator

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第6期12卷 486-498页

作者： jian XU Xiao-bo wu Meng-lian ZHAO Jun-yi SHEN Institute of VLSI Design Zhejiang University Hangzhou 310027 China

A low power high performance Delta-Sigma modulator for portable measurement applications is presented. To reduce power consumption while maintaining high performance, a fully feedforward architecture with a comprehensive system-level design is implemented. As a key building block, a novel power efficient current mirror operational transconductance amplifier (OTA) with a fast-settling less-error switched-capacitor common-mode feedback (SC CMFB) circuit is introduced, and the effects of both gain nonlinearity and 1/f noise of OTA are discussed. A new method to determine the voltage gain of an OTA is also proposed. The bottom terminal parasitic effect of poly-insulator-poly (PIP) capacitors is considered. About an extra 20% of capacitance is added to the total capacitance load. A power and area efficient resonator is adopted to realize a coefficient of 1/90 for 50% power and 75% area reduction compared with conventional designs. The chip is implemented in a low cost 0.35 μm complementary metal oxide semiconductor (CMOS) process. The total power consumption is 20 μW with a 1.5 V supply, and the measured dynamic range (DR) is 95 dB over a 1 kHz bandwidth. Experimental results show that a high figure-of-merit (FOM) is achieved for the designed modulator in comparison with those from the literature.

关键词： Low power High performance Power efficient OTA and resonator Delta-Sigma modulator

Synthesis of oleanolic disaccharide derivatives

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Chinese Chemical Letters 2012年第4期23卷 403-406页

作者： Shu Chen Pei jian bo wu Fan Lei Shan Qian Li Hai Yong wu Key Laboratory of Drug Targeting and Drug Delivery System of the Education Ministry Department of Medicinal ChemistryWest China School of PharmacySichuan UniversityChengdu 610041China Bioengineering College Xihua UniversityChengdu 610039China

Oleanolic acid 1 exists widely in food,medicinal herbs and other plants and possesses many attractive biological activities. Recently,some oleanolic derivatives were reported to have interesting anti-tumor ***,using association principle of drug design,OA disaccharide 17 was designed and synthesized by coupling a-L-rhamnopyranosyl-（1→2）-a-L-arabinopyranosyl disaccharide moiety,which has proved to be a unique sugar sequence with strongly antitumor activity,and modified OA with a nitrile at C-17.

关键词： Oleanolic acid Rhamnopyranosyl Arabinopyranosyl Anti-tumor Association principle

Synthesis of the major metabolites of Tolvaptan

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Chinese Chemical Letters 2012年第12期23卷 1343-1346页

作者： Wei Li Wan jian bo wu Fan Lei Xiao Long Li Li Hai Yong wu Key Laboratory of Drug Targeting and Drug Delivery System of the Education Ministry Department of Medicinal ChemistryWest China School of PharmacySichuan University

Tolvaptan is a nonpeptide arginine vasopressin （AVP） V2-receptor antagonist and used in the treatment of heart failure, cirrhosis, syndrome of inappropriate antidiuretic hormone secretion or other high-volume capacity of hyponatremia. The metabolites of tolvaptan are mainly produced by CYP3A4, including two major compounds named DM-4103 and DM-4107. Herein, the chemical synthesis of those two metabolites is described in this article for further study.

关键词： Tolvaptan Metabolites Synthesis

Hydrological response characteristics of landslides under typhoon-triggered rainstorm conditions

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China Geology 2020年第3期3卷 455-461页

作者： Tai-li Zhang Ai-guo Zhou Qiang Sun He-sheng Wang jian-bo wu Zheng-hua Liu Nanjing Center China Geological SurveyMinistry of Natural ResourcesNanjing 210016China China University of Geosciences Wuhan 430074China Geological Environment Monitoring Institute of Zhejiang Province Hangzhou 310007China

Many landslide disasters,which tend to result in significant damage,are caused by typhoon-triggered *** this case,it is very important to study the dynamic characteristics of the hydrological response of landslide bodies since it enables the early warning and prediction of landslide disasters in typhoon *** investigate the dynamic mechanisms of groundwater in a landslide body under typhoon-triggered rainstorm conditions,the authors selected the landslide occurring in Zhonglin Village,Wencheng County,China(also referred to as Zhonglin Village landslide)as a case *** transient seepage field characteristics of groundwater in the landslide body were simulated with two different rainfall models by using the finite element method(FEM).The research results show that the impact of typhoon-triggered rainstorms on landslides can be divided into three stages:(i)Rapid rise of groundwater level;(ii)infiltration of groundwater from the surface to deeper level,and(iii)surface runoff ***,the infiltration rate of groundwater in the landslide body is mainly affected by the intensity of typhoon-induced *** can be deduced that higher rainfall intensity leads to a greater potential difference and a higher infiltration *** rainfall intensity also determines the development mode of landslide deformation and destruction.

关键词： Typhoon-triggered rainstorm Landslide Seepage Hydrological response Hydrogeological survey engineering Geological disaster survey engineering Zhejiang Province China

Inhibition of tumor necrosis factor-α reduces alveolar septal cell apoptosis in passive smoking rats

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Chinese Medical Journal 2008年第7期121卷 597-601页

作者： ZHANG Cheng CAI Shan CHEN Ping CHEN jian-bo wu Jie wu Shang-jie ZHOU Rui Department of Respiratory Medicine Second Xiangya Hospital ofCentral-South University Changsha Hunan 410011 China

Background Recent studies have revealed that lung cell apoptosis plays an important role in pathogenesis of cigarette-induced chronic obstructive pulmonary disease （COPD）. Tumor necrosis factor alpha （TNF-α） is one of the most important cytokines which are involved in COPD. This study aimed at investigating the influence of its inhibitor, recombinant human necrosis factor-alpha receptor II：lgG Fc fusion protein （rhTNFR：Fc） on alveolar septal cell apoptosis in passive smoking rats. Methods Forty-eight rats were randomly divided into a normal control group, a passive smoking group, an rhTNFR：Fc intervention group and a sham intervention group. The passive smoking rats were treated by exposure to cigarette smoking daily for 80 days. After smoking for one month the rhTNFR：Fc intervention group was treated with rhTNFR：Fc by subcutaneous injection, the sham intervention group injected subcutaneously with a neutral preparation （normal saline 0.1 ml, manicol 0.8 ml, cane sugar 0.2 mg, Tris 0.024 mg as a control. Lung function was determined and the levels of TNF-a in serum and broncho-alveolar lavage fluid （BALF） were measured with enzyme-linked immunosorbnent assay （ELISA）. Lung tissue sections stained by hematoxylin and eosin （HE） were observed for study of morphological alternations. Mean linear intercept （MLI） and mean alveolar numbers （MAN） were measured and the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling （TUNEL） method was carried out to determine the percentage of positive cells and distribution of apoptotic cells. Results Increased MLI and decreased MAN were found in the passive smoking group compared with both the normal control group and the rhTNFR：Fc intervention group （P〈0.05）. Forced expiratory volume in 0.3 second （FEVo.3）/forced vital capacity （FVC） and peak expiratory flow （PEF） were lower in the passive smoking group than that in the normal control group （P〈0.05）. Compared with the sham intervention group, FEVo.3/FVC and PEF increa

关键词： tumor necrosis factor alpha chronic obstructive pulmonary disease apoptosis recombinant human tumor necrosis factor-Fc

The Mechanism of Heating Rate on the Secondary Recrystallization Evolution in Grain Oriented Silicon Steel

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Journal of wuhan University of Technology(Materials Science) 2025年第1期40卷 275-282页

作者： GAO Qian LI Jun WANG Xianhui CAO Laifu GONG jian LI bo Central Iron and Steel Research Institute Group Beijing 100081China Shougang Zhixin Electromagnetic Material R&D(Beijing)Co. Ltd.Beijing 101300China Beijing Shougang Co. Ltd.Qian’an 064404China

Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were *** illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically *** effect of precipitate ripening on the Goss texture and magnetic property was *** indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate *** recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}oriented grains growing abnormally and a magnetic induction intensity of ***,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss ***,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 *** a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this *** heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties.

关键词： high temperature annealing heating rate secondary recrystallization grain oriented silicon steel

Sky location of massive black hole binaries in the foreground of Galactic white dwarf binaries

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 97-108页

作者： Pan Guo Hong-bo Jin Cong-Feng Qiao Yue-Liang wu The International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences The School of Physical Sciences University of Chinese Academy of Sciences Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Institute of Theoretical Physics Chinese Academy of Sciences

For space-based gravitational wave （GW） detection,the main noise source for massive black hole binaries （MBHBs） is attributed to approximately 10～7double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratio ?DL/DLat the 95%confidence level,is enhanced by factors of ～*** angular resolutions,denoted by??s,are enhanced by a factor of ～*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.

关键词： space-based gravitational wave detection gravitational waves massive black hole binaries

ISOLATION AND STRUCTURE DETERMINATION OF XF-1,A NEW ANTHRACYCLINE ANTIBIOTIC

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Chinese Chemical Letters 1993年第9期4卷 787-790页

作者： Xu Guang YAN jian bo wu a.Institute of Medicinal Biotechnology,Chinese Academy of Medical Sciences,Beijing 100050Shao Zhao WANG b.Institute of Microbiology,Fuzhou 350007

A new Mutactimycin group antibiotic(XF-1)was isolated from the mycelium of Streptomyces sp.80-115 and its structure has been determined on the basis of its spectroscopical and chemical properties. XF-1 showed active a... 详细信息

关键词： ISOLATION AND STRUCTURE DETERMINATION OF XF-1,A NEW ANTHRACYCLINE ANTIBIOTIC OH Figure

GFRF R-CNN:Object Detection Algorithm for Transmission Lines

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Computers, Materials & Continua 2025年第1期82卷 1439-1458页

作者： Xunguang Yan Wenrui Wang Fanglin Lu Hongyong Fan bo wu jianfeng Yu Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China University of Chinese Academy of Sciences Beijing100049China Jingwei Textile Machinery Co. Ltd.Beijing100176China

To maintain the reliability of power systems,routine inspections using drones equipped with advanced object detection algorithms are essential for preempting power-related *** increasing resolution of drone-captured images has posed a challenge for traditional target detection methods,especially in identifying small objects in high-resolution *** study presents an enhanced object detection algorithm based on the Faster Regionbased Convolutional Neural Network(Faster R-CNN)framework,specifically tailored for detecting small-scale electrical components like insulators,shock hammers,and screws in transmission *** algorithm features an improved backbone network for Faster R-CNN,which significantly boosts the feature extraction network’s ability to detect fine *** Region Proposal Network is optimized using a method of guided feature refinement(GFR),which achieves a balance between accuracy and *** incorporation of Generalized Intersection over Union(GIOU)and Region of Interest(ROI)Align further refines themodel’s *** results demonstrate a notable improvement in mean Average Precision,reaching 89.3%,an 11.1%increase compared to the standard Faster *** highlights the effectiveness of the proposed algorithm in identifying electrical components in high-resolution aerial images.

关键词： Faster R-CNN transmission line object detection GIOU GFR