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TiO_2/云母复合颜料合成及其随角异色性能

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建筑材料学报 2009年第3期12卷 375-378页

作者：杨魁重庆大学材料科学与工程学院重庆400044 四川建筑职业技术学院土木工程系四川德阳618000

用偏钛酸制备TiOSO4溶液,采用液相均匀沉淀法制备出了含不同干涉色的TiO2/云母复合珠光颜料.利用SEM观察云母表面TiO2薄膜形貌.将具有不同干涉色的TiO2/云母涂层和不同色底漆交叉搭配后,制备出了可产生各种色彩效应的漆膜,并利用X-Rite... 详细信息

用偏钛酸制备TiOSO4溶液,采用液相均匀沉淀法制备出了含不同干涉色的TiO2/云母复合珠光颜料.利用SEM观察云母表面TiO2薄膜形貌.将具有不同干涉色的TiO2/云母涂层和不同色底漆交叉搭配后,制备出了可产生各种色彩效应的漆膜,并利用X-Rite多角度分光光度计对漆膜在不同角度下的颜色值CIE1976L*,a*,b*进行了测量.结果表明,该复合颜料涂层随角异色效应由表面清漆镜面反射、TiO2/云母涂层的干涉效应和底漆的漫反射作用共同形成;有并行排列效应颜料的干涉作用是产生涂层随角异色效应的直接原因;有不同干涉色复合颜料配合相同颜色底漆的涂层,其随角异色变化曲线形状接近,涂层色彩随观测角度的变化规律一致.

关键词：随角异色效应复合颜料纳米TiO2薄膜

Development of An Ionospheric Scintillation Monitor Using Single Frequency GPS Receiver

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Wuhan University Journal of Natural Sciences 2002年第2期7卷 189-194页

作者： Shu Di-fei Xu Ji-sheng School of Electronic Information Wuhan UniversityWuhan 430072HubeiChina

Besides their intended use in radio navigation, global positioning system (GPS) satellite signals provide convenient radio beacons for ionospheric studies. Among other propagation phenomena, the ionosphere affects GPS signal propagation through amplitude scintillations that develop after radio waves propagation through ionospheric electron density irregularities. This paper outlines the design, testing, and results of a specialized GPS receiver to monitorL-band scintillations. The scintillation monitor system consists of a commercial GPS receiver development kit with its software designed to log signal strength and carrier phase from up to 12 channels at one sample per second rate. Other prime features of the monitor include the data compression transmission and processing. Here is the fact that they are inexpensive and compact and therefore can be readily proliferated.

关键词： global positioning system ionosphere scintillation irregularity

Relative position determination of a lunar rover using the biased differential phase delay of same-beam VLBI

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Science China(Physics,Mechanics & Astronomy) 2011年第12期54卷 2284-2295页

作者： CHEN Ming LIU QingHui WU YaJun ZHAO RongBing dai ZhiQiang Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Beijing Aerospace Control Center Beijing 100094 China

When only data transmission signals with a bandwidth of 1 MHz exist in the rover, the position can be obtained using the differential group delay data of the same-beam very long baseline interferometry (VLBI). The relative position between a lunar rover and a lander can be determined with an error of several hundreds of meters. When the guidance information of the rover is used to determine relative position, the rover's wheel skid behavior and integral movement may influence the accuracy of the determined position. This paper proposes a new method for accurately determining relative position. The differential group delay and biased differential phase delay are obtained from the same-beam VLBI observation, while the modified biased differential phase delay is obtained using the statistic mean value of the differential group delay and the biased phase delay as basis. The small bias in the modified biased phase delay is estimated together with other parameters when the relative position of the rover is calculated. The effectiveness of the proposed method is confirmed using the same-beam VLBI observation data of SELENE. The radio sources onboard the rover and the lander are designed for same-beam VLBI observations. The results of the simulations of the differential delay of the same-beam VLBI observation between the rover and the lander show that the differential delay is sensitive to relative position. An approach to solving the relative position and a strategy for tracking are also introduced. When the lunar topography data near the rover are used and the observations are scheduled properly, the determined relative position of the rover may be nearly as accurate as that solved using differential phase delay data.

关键词： same-beam VLBI biased differential phase delay relative position determination lunar rover

Analysis of Bubble Behavior in a Horizontal Rectangular Channel under Subcooled Flow Boiling Conditions

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Fluid Dynamics & Materials Processing 2021年第1期17卷 81-95页

作者： Ke Sun Xiaoyu Hu Da Li Guodong Zhang kui Zhao Haiyang Zhao Shuzhan Bai School of Energy and Power Engineering Shandong UniversityJinan250061China

Experiments on subcooled flow boiling have been conducted using water in a rectangular flow *** to the coolant channel in internal combustion engines(IC engines),the flow channel in this experiment was asymmetrically *** images were captured using a high speed camera from the side view of the *** experimental conditions in terms of bulk temperature,bulk velocity,pressure and heat flux ranged from 65°C–75°C,0.25 m/s–0.75 m/s,1–1.7 bar and 490 kW/m2–700 kW/m2,*** the basis of these tests,a statistical analysis of the bubble size has been conducted considering a population of 1400 *** has been found that the mean Sauter bubble diameter increases with the decrease of subcooling,bulk velocity,pressure and increased heat flux.A modified correlation has been finally proposed to predict the mean Sauter bubble diameter under subcooled flow boiling conditions upstream of the onset of significant void,which shows good accuracy with the experimental results.

关键词： Subcooled flow boiling horizontal rectangular channel mean Sauter bubble diameter

A High Energy-Efficient Reconfigurable VLIW Symmetric Cryptographic Processor with Loop Buffer Structure and Chain Processing Mechanism

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Chinese Journal of Electronics 2017年第6期26卷 1161-1167页

作者： LI Wei ZENG Xiaoyang dai Zibin NAN Longmei CHEN Tao MA Chao State Key Lab of ASIC and System Fudan University Institute of Information Science and Technology Zhengzhou

By exploring symmetric cryptographic data level and instruction-level parallelism, the reconfigurable processor architecture for symmetric ciphers is presented based on Very-long instruction word(VLIW) structure. The application-specific instruction-set system for symmetric ciphers is proposed. As for the same arithmetic operation of symmetric ciphers, eleven kinds of reconfigurable cryptographic arithmetic units are designed by the reconfigurable technology. As to the requirement of high energy-efficient design, the loop buffer structure for instruction fetching unit is proposed to reduce the power consumption significantly with the same frequency as conventional, meanwhile, the chain processing mechanism is proposed to improve the cryptographic throughput without any area overhead. It has been fabricated with 0.18μm CMOS technology. The result shows that the processor can work up to 200 MHz, and the fourteen kinds of cryptographic algorithms were mapped in the processor, the encryption throughput of AES, SNOW2.0 and SHA2 algorithm can achieve 1.19 Gbps, 1.05 Gbps, and 407 Mbps respectively.

关键词： Symmetric cipher Energy-efficient VLIW processor Loop buffer structure Chain processing mechanism Reconfigurable

Flower-, wire-, and sheet-like MnO_2-deposited diatomites:Highly efficient absorbents for the removal of Cr(Ⅵ)

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Journal of Environmental Sciences 2015年第3期27卷 71-81页

作者： Yucheng Du Liping Wang Jinshu Wang Guangwei Zheng Junshu Wu Hongxing dai Key Lab of Advanced Functional Materials Ministry of Education College of Materials Science and Engineering Beijing University of Technology Laboratory of Catalysis Chemistry and Nanoscience Department of Chemistry and Chemical EngineeringCollege of Environmental and Energy Engineering Beijing University of Technology

Flower-, wire-, and sheet-like MnO2-deposited diatomites have been prepared using a hydrothermal method with Mn（Ac）2, KMnO4 and/or MnSO4 as Mn source and diatomite as support. Physical properties of the materials were characterized by means of numerous analytical techniques, and their behaviors in the adsorption of chromium（VI） were evaluated. It is shown that the IvinO2-deposited diatomite samples with different morphologies possessed high surface areas and abundant surface hydroxyl groups （especially the wire-like MnO2/diatomite sample）. The wire-like MnO2/diatomite sample showed the best performance in the removal of Cr（VI）, giving the maximum Cr（VI） adsorption capacity of 101 mg/g.

关键词： Morphological effect MnO2-deposited diatomite Cr(Vl) removalA dsorption efficiency

Uncertainty modeling of wind power frequency regulation potential considering distributed characteristics of forecast errors

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Protection and Control of Modern Power Systems 2021年第1期6卷 276-288页

作者： Cheng Yan Yi Tang Jianfeng dai Chenggen Wang shengjun Wu School of Electrical Engineering Southeast UniversityNanjingChina College of Automation Nanjing University of Posts and TelecommunicationsNanjingChina State Grid Jiangsu Electric Power Co. Ltd.Electric Power Research InstituteNanjingChina

Large-scale integration of wind power generation decreases the equivalent inertia of a power system, and thus makes frequency stability control challenging. However, given the irregular, nonlinear, and non-stationary characteristics of wind power, significant challenges arise in making wind power generation participate in system frequency regulation. Hence, it is important to explore wind power frequency regulation potential and its uncertainty. This paper proposes an innovative uncertainty modeling method based on mixed skew generalized error distribution for wind power frequency regulation potential. The mapping relationship between wind speed and the associated frequency regulation potential is established, and key parameters of the wind turbine model are identified to predict the wind power frequency regulation potential. Furthermore, the prediction error distribution of the frequency regulation potential is obtained from the mixed skew model. Because of the characteristics of error partition, the error distribution model and predicted values at different wind speed sections are summarized to generate the uncertainty interval of wind power frequency regulation potential. Numerical experiments demonstrate that the proposed model outperforms other state-of-the-art contrastive models in terms of the refined degree of fitting error distribution characteristics. The proposed model only requires the wind speed prediction sequence to accurately model the uncertainty interval. This should be of great significance for rationally optimizing system frequency regulation resources and reducing redundant backup.

关键词： Inertial response Primary frequency control Error distribution Mixed skew generalized error distribution Uncertainty modeling

Tackling the tumor microenvironment： what challenge does it pose to anticancer therapies？

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Protein & Cell 2014年第11期5卷 816-826页

作者： Fei Chen Xinyi Qi Min Qian Yue dai Yu Sun Institute of Health Sciences Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China School of Medicine Shanghai Jiao Tong University Shanghai 200025 China VA Seattle Medical Center Seattle WA 98108 USA Department of Medicine University of Washington Seattle WA 98195 USA

Cancer is a highly aggressive and devastating disease, and impediments to a cure arise not just from cancer itself. Targeted therapies are difficult to achieve since the majority of cancers are more intricate than ever imagined. Mainstream methodologies including chemotherapy and radiotherapy as routine clinical regimens frequently fail, eventually leading to pathologies that are refractory and incurable. One major cause is the gradual to rapid repopulation of surviving cancer cells during intervals of multiple-dose administration. Novel stressresponsive molecular pathways are increasingly unmasked and show promise as emerging targets for advanced strategies that aim at both de novo and acquired resistance. We highlight recent data reporting that treatments particularly those genotoxic can induce highly conserved damage responses in non-cancerous constituents of the tumor microenvironment （TMEN）. Master regulators, including but not limited to NF-kB and C/EBP-β, are implicated and their signal cascades culminate in a robust, chronic and genome-wide secretory program, forming an activated TMEN that releases a myriad of soluble factors. The damage-elicited but essentially off target and cell non-autonomous secretory phenotype of host stroma causes adverse consequences, among which is acquired resistance of cancer cells. Harnessing signals arising from the TMEN, a pathophysiological niche frequently damaged by medical interventions, has the potential to promote overall efficacy and improve clinical outcomes provided that appropriate actions are ingeniously integrated into contemporary therapies. Thereby, anticancer regimens should be well tuned to establish an innovative clinical avenue, and such advancement will allow future oncological treatments to be more specific, accurate, thor- ough and personalized.

关键词： tumor microenvironment DNA damage,secretory phenotype therapy resistance genotoxicity,clinical intervention

Molecular Simulation Studies on Basicity of Nitrogen-containing Compounds

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China Petroleum Processing & Petrochemical Technology 2009年第3期11卷 62-67页

作者： Wang Lixin Zhou Han dai Zhenyu Shen Xizhou SINOPEC Research Institute of Petroleum Processing Beijing 100083 Wuhan Institute of Technology

The DFT-based （density fimctional theory） ab initio quantum mechanical methods have been applied to study the basicity of the nitrogen-containing compounds in petroleum. The results have indicated that there is a distinct relationship between the protonation energy of nitrogen-containing compounds and their basicity. The more negative the protonation energy, the stronger the basicity is. It has been also found that aliphatic amines are more basic than pyridines or aromatic amines, and all these compounds are more basic than pyrroles. The addition of the aromatic rings can influence the basicity of anilines, while the 5- and 6-membered heterocyclic compounds function differently. The solvent properties may affect the basicity of these nitrogen-containing compounds.

关键词： nitrogen-containing compounds basicity quantum mechanics molecular simulation solvent effect