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Search Results: 1 - 10 of 34806 matches for " Gong-chu Shi "
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Leaching behavior of zinc and copper from zinc refinery residue and filtration performance of pulp under the hydrothermal process
Lei Cao,Ya-long Liao,Gong-chu Shi,Yu Zhang,Mu-yuan Guo
- , 2019, DOI: https://doi.org/10.1007/s12613-019-1706-z
Abstract: This study aims to investigate the leaching behavior and filtration performance of zinc refinery residue under hydrothermal conditions. The relationships between the structure and morphology of silicon in the leaching residue and the pulp filtration performance were explored by determining the pulp filtration speed, analyzing quantitatively the silicon content in the leachate, and characterizing the leaching residue structure. The results show that hydrothermal leaching induces the coagulation–hydrolysis of the silicon in solution, consequently altering the microstructure of the leaching residue, and that silicon oxygen tetrahedra ([SiO4]4?) form the main skeleton structure of the residue. The results obtained also show that the leaching rates of zinc and copper are 98.1% and 98.7%, respectively, and that the filtration speed is 526.32 L/(m2·h) under the conditions of sulfuric acid concentration of 140 g/L, leaching temperature of 160°C, leaching time of 3.0 h, oxygen partial pressure of 0.75 MPa, stirring speed of 600 r/min, and a liquid-to-solid ratio of 10 mL/g.
CMOS linear-in-dB VGA with DC offset cancellation for direct-conversion receivers
A CMOS Linear-in-dB VGA with DC Offset Cancellation for Direct-Conversion Receivers

Lei Qianqian,Chen Zhiming,Shi Yin,Chu Xiaojie,Gong Zheng,
雷倩倩
,陈治明,石寅,楚晓杰,龚正

半导体学报 , 2011,
Abstract: A low-power high-linearity linear-in-dB variable gain amplifier (VGA) with novel DC offset calibration loop for direct-conversion receiver (DCR) is proposed in this paper. The proposed VGA uses the differential-ramp based technique, digitally programmable gain amplifier (PGA) can be converted to analog controlled dB-linear VGA. An operational amplifier (OPAMP) utilizing an improved Miller compensation approach is adopted in this VGA design. The proposed VGA shows a 57dB linear range. The DC offset cancellation (DCOC) loop is based on a continuous time feedback that includes Miller effect and linear rang operation MOS transistor to realize large value capacitor and resistor to solve the DC offset problem, respectively. The proposed approach requires no external components and demonstrates excellent DCOC capability in measurement. Fabricated in SMIC 0.13 m CMOS technology, this VGA dissipates 4.5 mW from a 1.2 V supply voltage while occupying 0.58mm2 of chip area including bondpads. In addition, the DCOC circuit shows 500Hz high pass cutoff frequency (HPCF) and the measured residual DC offset at the output of VGA is less than 2 mV.
CMOS analog baseband circuitry for an IEEE 802.11 b/g/n WLAN transceiver
一种应用于IEEE 802.11 b/g/n无线局域网收发机的CMOS模拟基带电路

Gong Zheng,Chu Xiaojie,Lei Qianqian,Lin Min,Shi Yin,
龚正
,楚晓杰,雷倩倩,林敏,石寅

半导体学报 , 2012,
Abstract: 本文提出了一种应用于直接变频无线局域网收发机的模拟基带电路,该电路采用标准的0.13微米CMOS工艺实现,包括了采用有源RC方式实现的接收4阶椭圆低通滤波器、发射3阶切比雪夫低通滤波器、包含直流失调消除伺服环路的接收可变增益放大器及片上输出缓冲器。芯片面积共1.26平方毫米。接收基带链路增益可在-11dB至49dB间以2dB步长调节。相应地,基带接收输入等效噪声电压(IRN)在50 nV/sqrt(Hz) 至30.2 nV/ sqrt(Hz)间变化而带内输入三阶交调(IIP3)在21dBm至-41dBm间变化。接收及发射低通滤波器的转折频率可在5MHz、10MHz及20MHz之间选择以符合包含802.11b/g/n的多种标准的要求。接收基带I、Q两路的增益可在-1.6dB至0.9dB之间以0.1dB的步长分别调节以实现发射IQ增益失调校正。通过采用基于相同积分器的椭圆滤波器综合技术及作用于电容阵列的全局补偿技术,接收滤波器的功耗显著降低。工作于1.2V电源电压时,整个芯片的基带接收及发射链路分别消耗26.8mA及8mA电流。
Effects of Different Preparation Methods on the Properties of CeO2―ZrO2―Al2O3
JIAO Yi, TANG Shi-Yun, WANG Jian-Li, ZHU Qing-Chao, CHEN Yao-Qiang, GONG Mao-Chu
无机材料学报 , 2011, DOI: 10.3724/sp.j.1077.2011.00813
Abstract: Oxygen storage material of Ce0.5Zr0.5O2(12wt%)―Al2O3(CZA) was prepared by three different methods of coprecipitation, peptization and peptization―coprecipitation. The structure and physicochemical properties of materials were characterized by X―ray diffraction (XRD), N2 adsorption―desorption, oxygen pulse adsorption (OSC), H2―temperature programmed reduction (TPR) and O2―programmed desorption (O2―TPD). The XRD results demonstrate that all the samples have CeO2―ZrO2 cubic fluorite and γ―Al2O3 after calcined at 1000 . The results according to N2 adsorption―desorption show that the sample prepared by peptization―coprecipitation has higher specific surface area (146.2 m2/g), larger pore volume (0.5 mL/g), and the best distribution of the pore size. The results from OSC and H2―TPR indicate that the sample prepared by peptization―coprecipitation has the best performance of oxygen storage and reduction capacity. At the same time, the influence of different methods on the properties of samples after calcined at 1100 are discussed.
Life-cycle Environmental Friendly Construction of A Large Scale Project: A Case Study
Qian Shi,Ting Gong
Journal of Sustainable Development , 2009, DOI: 10.5539/jsd.v1n3p17
Abstract: Environmental friendly construction is one of the key tasks for the construction professionals. Large projects, which have great environmental and social impact, should act as the models of environmental friendly construction. In this paper, the authors have concluded some measures which are taken to promote positive impact of the World Expo Shanghai 2010 on environment and human health. The findings of this case study can be referred by construction professionals when conduction large scale projects.
A Surveying Study on Social Satisfaction to Current Doctor-Patient Relationship in China  [PDF]
Jingfen Shi, Yushi Jiang, Pei Hu, Yong Gong, Yuanfeng Li
Journal of Service Science and Management (JSSM) , 2015, DOI: 10.4236/jssm.2015.85071
Abstract: Objective: To survey social satisfaction to current doctor-patient relationship and to explore the influencing factors and improvement strategy. Methods: Survey 1167 people on internet by self-regulating questionnaire within the specified time and then make a statistical analysis. Results: The public’s satisfaction to doctor-patient relationship is just at the level of 51.11%. And the satisfaction to Pharmaceutical systems is 56.23%, to related governmental duties is 51.92%, to media coverage is 59.72%, to medical personnel is 65.68%, to patient is 65.74%. There are statistical differences between different ages, residences, educational backgrounds, occupation and medical payments (P < 0.05). Conclusion: The public’s satisfaction to current doctor-patient relationship is lower. It’s a system engineering to improve the doctor-patient relationship. It needs the medical personnel, patient, government and medium to participate in together and pay more effort to improve doctor-patient relationship.
PHOTOTHERMAL IONIZATION SPECTROSCOPY FOR SHALLOW DONOR IN Si1-xGex EPITAXIAL LAYER
外延Si1-xGex薄层中浅杂质的光热电离光谱

SHI XIAO-HONG,LIU PU-LIN,GONG DA-WEI,CHEN ZHANG-HAI,SHI GUO-LIANG,SHEN XUE-CHU,
石晓红
,刘普霖,龚大卫,陈张海,史国良,沈学础

物理学报 , 1997,
Abstract: The 2p± and 3p± excited lines of P donors in Si0.92Ge0.08 epitaxial layer have been observed using photothermal ionization spectroscopy.The ionization energy of P in Si0.92Ge0.08 is 45.51meV according to effective mass approach.The spectral lines of P in Si1-xGex compared with those in pure Si apparently broaden due to alloy disorder effect.
Construction of A Creative Instructional Design Model Using Blended, Project-Based Learning for College Students  [PDF]
Shi-Jer Lou, Chih-Chao Chung, Wei-Yuan Dzan, Ru-Chu Shih
Creative Education (CE) , 2012, DOI: 10.4236/ce.2012.37187
Abstract: The purpose of this study was to construct a blended, project-based learning creative instructional design model for university students that responds to the demands of the digital age, enhances student learning achievements in creativity, and cultivates student creative ability in independent thinking and innovation. This study organizes and analyzes blended learning, project-based learning, and the literature on creativity to summarize creative instructional design indicators for blended project-based learning, and it uses the fuzzy Delphi method for expert questionnaire analysis to filter the indicators most suited to university students. This study proposes that the four dimensions of creative instructional design are the following: 1) creative character traits; 2) ability in the creative process; 3) innovative product design, and 4) an instruc- tional environment for creativity, with a total of 23 design indicators. Based on the results of the expert questionnaire analysis and evaluation mechanisms, the levels of importance and primary consideration indicators of the design indicators are established. The results show that incorporation of creative instructional design in blended, project-based learning can sufficiently cover the content of the four dimensions of creativity and that this approach gains the approval of most experts. This instructional design model can be used as an indicator for creativity learning effect assessment of university students, as a basis for creative instructional design by teachers, and as a reference for creativity curricular planning in university engineering colleges. This model can effectively enhance student creativity learning effects and, in turn, achieve the objective of an overall elevation of national competitiveness.
Optical properties of UO2 and PuO2
Hongliang Shi,Mingfu Chu,Ping Zhang
Physics , 2009, DOI: 10.1016/j.jnucmat.2010.02.024
Abstract: We perform first-principles calculations of electronic structure and optical properties for UO2 and PuO2 based on the density functional theory using the generalized gradient approximation (GGA)+\emph{U} scheme. The main features in orbital-resolved partial density of states for occupied \emph{f} and \emph{p} orbitals, unoccupied \emph{d} orbitals, and related gaps are well reproduced compared to experimental observations. Based on the satisfactory ground-state electronic structure calculations, the dynamical dielectric function and related optical spectra, i.e., the reflectivity, adsorption coefficient, energy-loss, and refractive index spectrum, are obtained. These results are consistent well with the attainable experiments.
Is the universe rotating?
Shi-Chun Su,M. -C. Chu
Physics , 2009, DOI: 10.1088/0004-637X/703/1/354
Abstract: Models of a rotating universe have been studied widely since G{\"o}del \cite{1}, who showed an example that is consistent with General Relativity (GR). By now, the possibility of a rotating universe has been discussed comprehensively in the framework of some types of Bianchi's models, such as Type V, VII and IX \cite{2,3}, and different approaches have been proposed to constrain the rotation. Recent discoveries of some non-Gaussian properties of the Cosmic Microwave Background Anisotropies (CMBA) \cite{nG1,nG2,nG3,nG4,nG5,nG6,nG7}, such as the suppression of the quadrupole and the alignment of some multipoles draw attention to some Bianchi models with rotation \cite{bi1,bi2}. However, cosmological data, such as those of the CMBA, strongly prefer a homogeneous and isotropic model. Therefore, it is of interest to discuss the rotation of the universe as a perturbation of the Robertson-Walker metric, to constrain the rotating speed by cosmological data and to discuss whether it could be the origin of the non-Gaussian properties of the CMBA mentioned above. Here, we derive the general form of the metric (up to 2nd-order perturbations) which is compatible with the rotation perturbation in a flat $\Lambda$-CDM universe. By comparing the 2nd-order Sachs-Wolfe effect \cite{4,5,6,7,8} due to rotation with the CMBA data, we constrain the angular speed of the rotation to be less than $10^{-9}$ rad yr$^{-1}$ at the last scattering surface. This provides the first constraint on the shear-free rotation of a $\Lambda$CDM universe.
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