检索结果-南通市图书馆

An RF frontend circuit design of a compass and GPS dual-mode dual-channel image rejection radio receiver

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Semiconductors 2013年第8期34卷 127-132页

作者：张弓陈红林刘渭杨寒冰张丽娟王祥炜石磊胡思静王明照符卓剑 Guangzhou Runxin Information Technology co.ltd

This paper introduces a fully integrated low power consumption radio receiver frontend circuit for a compass（Beidou） and GPS dual mode dual channel system with 2.5 dB NF,1.02 mm^2 areas,and 8 mA of current in 0.18μm TSMC CMOS *** for a few passive components for input matching,other components such as an off-chip low noise amplifier or a balun are not *** a non-tunable passive image rejection filter,the receiver frontend can achieve around 60 dB gain and 34 dB image rejection.

关键词： compass(BeiDou) GPS CMOS receiver frontend active balun image rejection

Synthesis, Antibacterial Activities and Theoretical Studies of Benzopyranocoumarin Derivatives

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2015年第10期34卷 1606-1611页

作者：鲁光英方军 Boch Pharma.Technology (Shanghai) co.ltd

Three benzopyranocoumarins（OBH, OMH and ODH） were synthesized and characterized via IR, ^1H NMR and HRMS. The HB energy in OBH, OMH and ODH was performed with the density functional theory（DFT） [B3LYP/6-31G＊] method. The in vitro antibacterial activity of OBH, OMH and ODH against drug-sensitive S. aureus（S. aureus ATCC 29213） strain, MRSA strain（MRSA XJ 75302）, drug-sensitive S. epidermidis strain（S. epidermidis ATCC 14990） and methicillin-resistant S. epidermidis strain（MRSE XJ 75284） was evaluated by observing the minimum inhibitory concentration. The results showed that among the three compounds, ODH exhibited the most potent antibacterial activity.

关键词： benzopyranocoumarin density functional theory Staphylococcus aureus minimum inhibitory concentration

Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： Feng Zhang Chenyang Zhang Linlin Wu Wei Sun Hongliang Zhang Jianhua Chen Yong Pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group co.ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

Viscoelasticity of mixed polyacrylamide solution

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2008年第S1期15卷 443-446页

作者：徐丽娜 PetroChina Daqing Oilfield Engineering co.ltd

The viscoelastic behavior of polyacrylamide solution is crucial for its application in various *** mixed polyacrylamide solution was prepared by mixing polyacrylamide with different relative molecular masses according to the defined mass *** viscosity and elasticity of mixed polyacrylamide solution were separately tested with RS150 rheometer and capillary breakup extensional rheometer and compared with those of the single polyacrylamide solution which is directly provided by manufacturer without any *** results indicate that the mixed and single polyacrylamide solutions have the same shear viscosity and intrinsic ***,some mixed polyacrylamide solutions have higher elasticity than single polyacrylamide *** flow resistance of mixed polyacrylamide with higher elasticity is also greater than that of single polyacrylamide solution in porous *** paper presents an effective method of mixing polyacrylamides with different relative molecular masses,which can enhance the elasticity of polyacrylamide solution and flowing resistance through porous medium.

关键词： polyacrylamide viscosity elasticity flow resistance

Enteromorpha prolifera polysaccharide-Fe(Ⅲ) complex promotes intestinal development as a new iron supplement

在线全文

学校读者我要写书评

暂无评论

Science China Life Sciences 2025年第1期 219-231页

作者： Yingying Feng Yuying Wu Jialu Wang Zhenglin Dong Qian Yu Shuangshuang Xia Chunxue Liu Haihua Wang Xin Wu Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences CAS Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical AgricultureChinese Academy of Sciences ANYOU Biotechnology Group co.ltd Qingdao Seawin Biotech Group co. LTD

Iron is a crucial micronutrient, and its deficiency can have detrimental effects on the health of infants. Dietary polysaccharide-iron(Ⅲ) complexes(PICs) are promising for addressing iron deficiency due to their minimal adverse reactions and high iron absorption rate. This study aimed to investigate the effects of dietary Enteromorpha prolifera polysaccharide-Fe(Ⅲ) complex(EP-Fe) on newborns, using 3-day weaned piglets as the iron-deficiency model. Results showed that EP-Fe improved iron levels and promoted intestinal development in piglets. Transcriptome sequencing revealed that EP-Fe increased the survival of intestinal epithelial cells under hypoxia by upregulating the expression of genes that promote the development of the vascular system. Additionally, EP-Fe enhanced the mucosal barrier functions by inhibiting myosin light chain kinase(MLCK)/phosphorylated myosin light chain(p-MLC) signaling pathway to increase the expression of intestinal tight junction proteins. Furthermore, the 16S r RNA gene sequencing of gut microbiota showed that EP-Fe promoted the enrichment of Bacteroides＿fragilis and other gut microbes that can metabolize carbohydrates. In conclusion, EP-Fe is an effective iron supplement for newborns, and it can be developed as a comprehensive nutritional supplement.

关键词：

同方期刊数据库

Synthesis and Characterization of Long Chain Semiaromatic Polyamides based on Undecanediamine

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2012年第4期27卷 689-693页

作者：王文志 Zhuzhou Times New Material Technology co.ltd

Long chain semiaromatic polyamides with high molecular weight were synthesized by the reactions of undecanediamine with various aromatic diacids,and characterized by fourier transform infrared spectra（FT-IR） and nuclear magnetic resonance（1H-NMR）.The thermal behaviors were determined by differential scanning calorimetry（DSC） and thermogravimetric analysis（TGA）.The solubility,dynamic mechanical,physical and mechanical properties of the polyamides were also *** experimental results show that the polyamides with high molecular weights are obtained only the PH value of the polyamides salt are in the range of *** melting temperatures and the glass transition temperatures of the polyamides increase with the increase of the rigidity of aromatic diacids,and are near to those of poly（nonamethylenetere-phthalamide）（PA9T）.

关键词： polyamide undecanediamine semiaromatic

Properties of electrodeposited amorphous Fe-Ni-W alloy deposits

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2006年第6期7卷 1289-1294页

作者：何凤姣王淼陆欣 college of Chemistry and Chemical Engineering Hunan University Yingcai Technology co.ltd

A new technique of electroplating amorphous Fe-Ni-W alloy deposits was *** structure and morphology o Fe-Ni-W alloy deposit were detected by XRD and *** friction and wear behavior of Fe-Ni-W alloy deposit were studied and compared with that of chromium *** corrosion properties against 5% sodium chloride,5% sulfuric acid and 5% sodium hydroxide were also *** experimental results indicate that Fe-Ni-W alloy deposits have superior properties against wea than hard chromium deposits under dry sliding *** oil sliding condition,except their better wear resistance,the deposits can protect their counterparts against *** deposits plated on brass and AISI 1045 steel show good behavior against corrosion o 5% sodium chloride,5% sulfuric acid and 5% sodium *** bath of electroplating amorphous Fe-Ni-W alloy deposits is environmentally friendly and would find widely use in industry.

关键词： electrodeposition amorphous Fe-Ni-W alloy deposits wear resistance corrosion resistance

Damping forced oscillations in power system via interline power flow controller with additional repetitive control

在线全文

学校读者我要写书评

暂无评论

Protection and control of Modern Power Systems 2021年第1期6卷 264-275页

作者： Shirui Feng Xi Wu Zhenquan Wang Tao Niu Qiong Chen Jiangsu Electric Power Design Institute co.ltd China Energy Engineering Group Co.LtdNanjingChina college of Electrical Engineering Southeast UniversityNanjingChina

With the continuous expansion of power systems and the application of power electronic equipment, forced oscillation has become one of the key problems in terms of system safety and stability. In this paper, an interline power flow controller (IPFC) is used as a power suppression carrier and its mechanism is analyzed using the linearized state-space method to improve the system damping ratio. It is shown that although the IPFC can suppress forced oscillation with well-designed parameters, its capability of improving the system damping ratio is limited. Thus, combined with the repetitive control method, an additional repetitive controller (ARC) is proposed to further dampen the forced power oscillation. The ARC control scheme is characterized by outstanding tracking performance to a system steady reference value, and the main IPFC controller with the ARC can provide higher damping, and further reduce the amplitude of oscillations to zero compared with a supplementary damping controller (SDC). Simulation results show that the IPFC with an ARC can not only greatly reduce the oscillation amplitude, but also actively output the compensation power according to the reference value of the ARC tracking system.

关键词： Forced oscillation Interline power flow controller(IPFC) Additional repetitive control(ARC) Linearized state-space method

A reconfigurable OTA-C baseband filter with wide digital tuning for GNSS receivers

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Semiconductors 2010年第9期31卷 94-98页

作者：潘文光马成炎甘业兵叶甜春 Institute of Microelectronics Chinese Academy of Sciences Hangzhou Zhongke Microelectronics co.ltd

The design of a digitally-tunable sixth-order reconfigurable OTA-C filter in a 0.18-μm RFCMOS process is *** filter can be configured as a complex band pass filter or two real low pass *** improved digital automatic frequency tuning scheme based on the voltage controlled oscillator technique is adopted to compensate for process *** extended tuning range（above 8：1） is obtained by using widely continuously tunable transconductors based on digital *** the complex band pass mode,the bandwidth can be tuned from 3 to 24 MHz and the center frequency from 3 to 16 MHz.

关键词： reconfigurable filter wide tuning digital frequency tuning