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Acta Geologica Sinica(English Edition) 2007年第4期81卷 525-538页

作者： wang deming Key Laboratory of Orogenic Belts and Crustal Evolution Department of Geology Peking University Beijing 100871

ZosterophyUum longa sp. nov. is reported from the Lower Devonian Pingyipu Formation, Jiangyou District, northern Sichuan of China. This new plant has vertically elongate sporangia differing from all known species of Zosterophyllum, demonstrating morphological variations in Zosterophyllophytina. New materials of Zosterophyllum yunnanicum from the Lower Devonian Xujiachong Formation, Qujing District, eastern Yunnan of China show that fertile axes of this species are anisotomous or pseudomonopodial or K-shaped in branching. Sometimes fertile lateral axes are very short and bear an axillary axis at the dividing point. Distinct thickening occurs along the whole margin of a sporangium, with sporangial lobes undeveloped. The evolution of ZosterophyUum is tentatively discussed. A biostratigraphic method of Gerrienne and Streel is introduced and applied to dating of the Lower Devonian Xujiachong Formation, which is considered as of the late Pragian-early Emsian.

关键词： Zosterophyllum longa sp. nov. Z. yunnanicum biostratigraphic method Early Devonian,Xujiachong Formation South China

A 2 Kbits Low Power EEPROM for Passive RFID Tag IC

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Chinese Journal of Electronics 2022年第1期31卷 18-24页

作者： HU Jianguo wang deming WU Jing School of Microelectronics Science and Technology Sun Yat-sen University School of Physics and Telecommunication Engineering South China Normal University Development Research Institute of Guangzhou Smart City

This paper presents a low power consumption and low cost electrically erasable programmable read-only memory(EEPROM) for radio frequency identification(RFID) tag chip. A read-write circuit with parallel input and serial output is proposed. Only one sensitive amplifier is used to read the data in memory,which can effectively reduce the power consumption of the read operation. Because the tag may be read or written while moving, the internal voltage may change in a wide range. Therefore, this paper designs a charge pump and its control circuit with wide voltage working *** proposed EEPROM is integrated into an RFID tag chip and fabricated using a 180 nm complementary metal-oxide semiconductor(CMOS) process. Experimental results show that the circuit can work in the input voltage range of 1 V to 1.8 V, and the minimum current of read operation and write operation is 0.68 μA and 30 μA respectively, which has the characteristic of low power consumption.

关键词： wide voltage working range low power EEPROM EPROM control circuit serial output input voltage range radio frequency identification tag chip complementary metal-oxide semiconductor process passive RFID tag IC read-write circuit low-power electronics internal voltage low cost electrically erasable programmable read-only memory parallel input CMOS integrated circuits radiofrequency identification RFID tag chip sensitive amplifier low power consumption read operation CMOS process

VLSI Implementation of Area and Power Efficient Digital Control Circuit for HF RFID Tag Chip

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Chinese Journal of Electronics 2020年第1期29卷 82-88页

作者： wang deming HU Jianguo wang Jianhui DING Yanyu WU Jing School of Physics and Telecommunication Engineering South China Normal University Hong Kong Applied Science and Technology Research Institute Company Limited

A fully integrated area efficient digital control circuit based on the ISO/IEC 15693 protocol is proposed for high frequency RFID tag chip. The proposed circuit is mainly composed of pulse position modulation decoder, Manchester encoder, anticonllision, low power circuit and other control logic. It supports six different data rates, namely, low or high data rate with one subcarrier(6.62 or 26.48 Kbit/s), low or high data rate with two subcarriers(6.67 or 26.69 Kbit/s), fast data rate with one subcarrier(13.24 or 52.97 Kbit/s). The proposed digital control circuit was integrated in an RFID tag IC and was fabricated using a 0.18-μm 2 P6 M CMOS process with an area of 306μm by 326μm which is smaller than the existing designs. Besides of small area, the circuit has an advantage of low power with a power consumption of less than 50μW.

关键词： RFID Digital control circuit Low power VLSI

Archaeopteris halliana from the Late Devonian(Famennian)of Anhui Province,China

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Acta Geologica Sinica(English Edition) 2009年第3期83卷 479-491页

作者： GUO Yun wang deming Key Laboratory of Orogenic Belts and Crustal Evolution MOE Department of Geology Peking University Beijing 100871 China

New materials from the Upper Devonian （Famennian） Wutong Formation of Chizhou District, Anhui Province, South China, allow description of fertile and sterile characters of Archaeopteris halliana. This plant has penultimate axes attached by sterile leaves and paired ultimate branches in the same ontogenetic spiral. Sterile leaves are narrowly cuneate in shape and bear distal margins dissected deeply. These leaves are spirally arranged on sterile ultimate axes. Non-laminated sporophylls occur spirally on the ultimate axes and bifurcate once or twice. Elongate sporangia with longitudinal dehiscence are borne adaxially below or above the dividing points of the sporophylls. Despite the leaf shape resembling that of Archaeopteris macilenta, our plant is assigned to A. halliana because of its non-laminated sporophylls. Fertile characters should be given priority or enough consideration in identifying species of Archaeopteris.

关键词： progymnosperms Archaeopteris sporophyll Late Devonian Wutong Formation AnhuiProvince South China

Hamatophyton from the Late Devonian of Anhui Province,South China and Evolution of Sphenophyllales

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Acta Geologica Sinica(English Edition) 2009年第3期83卷 492-503页

作者： wang deming GUO Yun Key Laboratory of Orogenic Belts and Crustal Evolution MOE Department of Geology Peking University Beijing 100871 China

Well-preserved specimens of Hamatophyton verticillatum collected from the Upper Devonian （Famennian） Wutong Formation of Chaohu district, Anhui Province, South China, display more complete fertile axes in three orders and multiple divisions. Comparisons indicate that Hamatophyton possibly does not have palmate planate sterile leaves but hook-like linear ones with rare divisions. We propose seven definitive characters of Sphenophyllales：（1） completely whorled lateral organs; （2） sterile leaves; （3） strobili; （4）＂sporangiophores＂ or stalks with reflexed tips bearing sporangia; （5） three- or four-ribbed primary xylem; （6） exarch maturation of primary xylem; and （7） secondary xylem. The Sphenophyllales probably originated from the Iridopteridales based on similarities in whorled lateral organs, ribbed primary xylem and peripheral protoxylem strands. In transition from Iridopteridales to Sphenophyllales, morphological changes involve partially whorled to completely whorled lateral organs, sterile ultimate appendages to leaves, and fertile ultimate appendages to ＂sporangiophores＂/stalks with bracts; anatomical modifications include configuration and maturation of primary xylem, and presence of secondary xylem.

关键词： Hamatophyton, Sphenophyllales Iridopteridales, Sphenopsida, Late Devonian, WutongFormation, Anhui Province

Effect of dosage of expandable graphite,dimethyl methylphosphonate,triethanolamine,and isocyanate on fluidity,mechanical,and flame retardant properties of polyurethane materials in coal reinforcement

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International Journal of Mining Science and Technology 2016年第2期26卷 345-352页

作者： Hu Xiangming wang deming Cheng Weimin Key Laboratory of Gas and Fire Control for Coal Mines of Ministry of Education Faculty of Safety EngineeringChina University of Mining and Technology Key Laboratory of Mine Disaster Prevention and Control College of Resource and Environmental EngineeringShandong University of Science and Technology Department of Resources and Environment Binzhou University

In this study,orthogonal experiments were conducted to investigate the influence of expandable graphite(EG),dimethyl methylphosphonate(DMMP),triethanolamine(TEA),and isocyanate content on the compressive and bonding strengths,oxygen index,and fluidity of rigid polyurethane foam(RPUF).The results revealed that EG significantly increased the oxygen index of RPUF,enlarged the diameter of foam cells,and decreased the cell-closed content in foam;thus,leading to a pressure drop in ***,excessive EG was capable of reducing the fluidity of polyurethane *** exhibited significant influence on the compressive strength of RPUF,which dropped initially,and then *** had a remarkable effect on the flame retardant property and compressive strength of *** strength of RPUF initially displayed an increase followed by a decrease with increasing dosage of DMMP,and achieved the maximum value at DMMP dosage of 4%.DMMP could effectively reduce the diameter of RPUF cells leading to an increase in the percentage of close area in *** displayed the flame-retardation effects mainly in the gas phase leading to a significant enhancement in the oxygen index of ***,the compressive strength and bonding strength of RPUF decrease significantly with the increase of isocyanate content due to the increased blowing efficiency by the CO_*** oxygen index and flowing length of foam increased with the increase in isocyanate dosage.

关键词： Rigid polyurethane foam Expandable graphite Compressive strength Flame retardant Scanning electron microscopy(SEM) Microstructure

Study of the features of outburst caused by rock cross-cut coal uncovering and the law of gas dilatation energy release

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International Journal of Mining Science and Technology 2015年第3期25卷 453-458页

作者： Yu Baohai Su Chengxiang wang deming State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology Faculty of Safety Engineering China University of Mining and Technology Key Laboratory of Gas and Fire Control for Coal Mines China University of Mining and TechnologyMinistry of Education

To study the law of gas dilatation energy release of rock cross-cut coal uncovering face, according to the analysis of the physical parameters distribution features of coal and rock mass in front of crosscut face,the equations of elastic potential of coal and gas dilatation energy theory were set up to process a contrast calculation of the sizes of two kinds of energy. The results show that gas dilatation energy is the uppermost energy source causing outburst occurrence. Furthermore, the mathematical model of spherical flow field gas dilatation energy release was established and MATLAB software was applied to make a numerical calculation analysis on the law of gas dilatation energy release. The results indicate that the gas dilatation energy is closely related to gas parameters and its energy index does reflect the possibility of coal seam outburst.

关键词： Rock cross-cut coal uncovering Gas dilatation energy Numerical calculation Coal and gas outburst

Synergistic effects of expandable graphite and dimethyl methyl phosphonate on the mechanical properties, fire behavior, and thermal stability of a polyisocyanurate-polyurethane foam

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International Journal of Mining Science and Technology 2013年第1期23卷 13-20页

作者： Hu Xiangming wang deming wang Shuailing Key Laboratory of Coal Resources and Mine Safety School of Safety Engineering China University of Mining & Technology Department of City & Environmental Science Binzhou University Binzhou 256603 China

In this study, a series of flame-retardant polyisocyanurate-polyurethane (PIR-PUR) foams were prepared using various concentrations (0-25% by weight) of expandable graphite (EG) and dimethyl methyl phosphonate (DMMP) (0-7% by weight). The effect of these additives on the properties of the PIR-PUR foams, including physico-mechanical, morphological, flame retardancy, and thermal stability, was studied. Increasing amounts of EG in the PIR-PUR foam caused a significant drop in the compression strength. However, DMMP caused the mechanical properties of PIR-PUR foam to improve compared to foam filled with EG alone. The flame retardancy of PIR-PUR foams containing both EG and DMMP was enhanced significantly compared to EG filled foams. Thermogravimetric analysis (TGA) indicated that EG enhances the thermal stability of PIR-PUR foams but that DMMP decreased it. The morphology of the residual char provided conclusive evidence for the weak thermal stability of foams filled with DMMP.

关键词： Expandable graphite Dimethyl methyl phosphonate Fire behavior Thermal stability PIR–PUR foam

A new design of foaming agent mixing device for a pneumatic foaming system used for mine dust suppression

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International Journal of Mining Science and Technology 2016年第2期26卷 187-192页

作者： wang deming Lu Xinxiao wang Hetang Chen Mingjie School of Safety Engineering China University of Mining and Technology State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology Key Laboratory of Gas and Fire Control for Coal Mines of Ministry of Education China University of Mining and Technology

To overcome the drawbacks of the conventional foam technology used for dust suppression,including large pressure loss,high water pressure and low driving pressure,a new pneumatic foaming system is *** an original design of foaming agent mixing device is proposed,and its performance is investigated and evaluated under different pressure *** results show that the maximum absorption amount increases by 2.9-6.7 times at a pressure compensation of 0.04-0.2 MPa compared with no pressure *** pressure loss and pressure fluctuation both reduce significantly with increasing pressure *** critical outlet pressure increases by30.4-240%.Field application indicates that the proposed mixing device ensures the reliable addition of foaming agent used for foam dust *** effect of foam on dust suppression is remarkable,and the economic cost of foam is ***,there is reason to believe that the new mixing device will greatly promote foam technology to be widely used for suppressing dust in underground coal mines.

关键词： Compressed air jet Pressure compensation Foam Dust suppression

A High-Performance RSA Coprocessor Based on Half-Carry-Save and Dual-Core MAC Architecture

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Chinese Journal of Electronics 2018年第1期27卷 70-75页

作者： DING Yanyu HU Jianguo wang deming TAN Hongzhou School of Information Science and Technology Sun Yat-sen University

This research focuses on the methods to improve the throughput and lower the power for low cost RSA coprocessors. We proposed the following optimized methods: 1. A fast half-carry-save Montgomery modular multiplication algorithm suitable for hardware implementation; 2. A high-speed dual-core multiplier accumulator architecture to optimize the critical path; 3. Several lowpower optimization schemes for the RSA coprocessor. The design has been implemented with TSMC 90 nm technology, and the experimental results show that the critical path is 2.71 ns, the power consumption is just 9.76 m W and the throughput can reach 381.57 kbps. Compared with relative works, our design is featured by the minimal power and the best overall performance, thus it is most suitable for applications in low-power systems.

关键词： RSA coprocessor Montgomery multiplication Half-carry-save Dual-core MAC