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Rational design strategies of Cu-based electrocatalysts for CO_(2) electroreduction to C_(2) products

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Journal of Energy Chemistry 2022年第8期31卷 63-82,I0003页

作者： Shuo Liu Baoshan zhang lihong zhang Jie Sun Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China

Electrochemical reduction of CO_(2)(CO_(2)RR)to high value-added chemicals is an effective way to remove excess CO_(2) from the *** to the unique propensity of Cu for valuable hydrocarbons,Cu-based electrocatalysts are the most potential catalysts that allow the conversion of CO_(2) into a variety of C_(2) products such as ethylene and *** design of Cu-based catalysts can improve their directional selectivity to C_(2) ***,in this review,we summarize the recent progress in the mechanistic studies of Cu-based catalysts on reducing CO_(2) to C_(2) *** focus on three key strategies for efficiently enhancing electrocatalytic performance of Cu-based catalysts,including tuning electronic structure,surface structure,and coordination *** correlation between the structural characteristics of Cu-based catalysts and their activity and selectivity to C_(2) products is ***,we discuss the challenges in the field of CO_(2) electroreduction to C_(2) products and provide the perspectives to design efficient Cu-based catalysts in the future.

关键词： Carbon dioxide Cu-based catalysts Mechanisms Active site regulation

A Low-Power Low-Cost 780MHz CMOS FSK Receiver for Short-Range Wireless Communication

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Chinese Journal of Electronics 2016年第2期25卷 220-226页

作者： YIN Yadong YANG Yuanting zhang lihong College of Physics and Information Engineering Fuzhou University Fujian Polytechnic of Information Technology Fujian Jiangxia University

This paper presents a low-power low-cost780 MHz CMOS Frequency shift keying(FSK) receiver for short-range wireless communication. A current-reused Low power amplifier(LNA) and a single-balance passive mixer are employed to cut down the current consumption of the RF frontend in receiver. A 3rd-order active-RC complex filter with reconfigurable bandwidth is implemented and a novel automatic tuning circuit is used in the filter to eliminate the negative effect of the Process, voltage, temperature(PVT) variations. A novel replica-circuit master-slave automatic tuning circuit and a discrete-time differentiator are employed in demodulator to keep the demodulation performances from the PVT variations and the frequency offset of Intermediate frequency(IF). The receiver is fabricated in 0.18μm CMOS and occupies a chip area of about 0.97mm2. It can achieve a sensitivity of –83.7d Bm and a tolerance of IF range from 1.5MHz to 3.7MHz with a 4.7m A current consumption under a 1.8V supply.

关键词： CMOS integrated circuit Current reused Frequency offset tolerance Frequency shift keying(FSK) demodulation Low power Receiver

Precipitation behaviors of X70 acicular ferrite pipeline steel

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Journal of University of Science and Technology Beijing 2006年第6期13卷 523-527页

作者： Hao Yu Yi Sun Qixiang Chen Haitao Jiang lihong zhang Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China Jinan Iron ＆ Steel Group Co. Jinan 250101 China

The morphology, structure, and chemical composition of precipitates in the final microstructure of Nb-V-Ti microalloyed X70 acicular ferrite pipeline steel were investigated using transmission electron microscopy （TEM） and energy dispersive X-ray spectroscopy （EDS）. Precipitates observed by TEM can be classified into two groups. The large precipitates are complex compounds that comprise square-shaped TiN precipitate as core with fine Nb-containing precipitate nucleated on pre-existing TiN precipitate as caps on one or more faces at high temperature. In contrast, the fine and spherical Nb carbides and/or carbonitrides precipitate heterogeneously on dislocations and sub-boundaries at low temperature. From the analysis in terms of thermodynamics, EDS and chemical cornposition of the steel, NbC precipitation is considered to be the predominant precipitation behavior in the tested steel under the processing conditions of this research.

关键词： pipeline steel acicular ferrite microstructure carbonitride precipitation behavior thermodynamics

Spatial resolved temperature measurement based on absorption spectroscopy using a single tunable diode laser

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Acta Mechanica Sinica 2010年第1期26卷 147-149页

作者： Xilong Yu Fei Li lihong Chen Xinyu zhang Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences100190 Beijing China

A novel method based on wavelength-multiplexed line-of-sight absorption and profile fitting for nonuniform flow field measurement is reported. A wavelength scanning combing laser temperature and current modulation WMS scheme is used to implement the wavelength-multi- plexed-profile fitting method. Second harmonic （2f） signal of eight H20 transitions features near 7,170 cm^-1 are measured in one period using a single tunable diode laser. Spatial resolved temperature distribution upon a CH4/air premixed flat flame burner is obtained. The result validates the feasibility of strategy for non-uniform flow field diagnostics by means of WMS-2f TDLAS.

关键词： WMS-2fTDLAS - Profile fitting Spatial resolved - Temperature measurement

Efficacy of Bushenjianpi prescription on autoimmune premature ovarian failure in mice

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Journal of Traditional Chinese Medicine 2017年第5期37卷 667-674页

作者： Feng Guilin Lin Meijiao Zhou Xiaolin zhang lihong Li Jing Ouyang Jingfeng Gynecological Department of Traditional Chinese Medicine School Clinic Nanyang Normal University College Department of Pediatrics Dongzhimen Hospital Affialited to Beijing University of Chinese Medicine Department of Traditional Chinese Medicine Nanyang Medical College Department of Oncology the Third People'Hospital of Zhengzhou City Department of Traditional Chinese Medicine Children' Hospital of Kaifeng Morphology Laboratory Experimental Research Center China Academy of Chinese Medical Sciences

OBJECTIVE: To assess the efficacy of Bushenjianpi prescription(BSJPP), a formula from Traditional Chinese Medicine, on a mouse model of autoimmune premature ovarian failure(POF) induced by mouse zona pellucida(ZP3) and to investigate the mechanisms underlying the ***: After randomization, POF was induced in the model mice by immunization with ZP3. One week later, mice received low(8.1 mg/kg), moderate(16.2 mg/kg) and high(32.4 mg/kg) doses of BSJPP by gastrogavage once daily for 90 days. Premarin(0.03 mg/kg) served as the positive group. Serum samples were collected 1 week after the last dose and stored at-20 ℃ for analysis. After cervical dislocation, the uterus and ovaries were collected aseptically for evaluation by histological assessment, scanning electron microscopy, immunohistochemical staining, and Western blot and reverse transcription-polymerase chain reaction ***: Serum E2 levels in POF model mice were decreased, whereas follicle-stimulating hormone(FSH) and luteinizing hormone(LH) levels were dramatically increased. Serum levels of E2,LH and FSH were reduced in POF model mice treated with BSJPP(moderate and high doses) and premarin. Anti-bone morphogenetic protein 15(BMP-15) and connexin 43(Cx43) were repressed in autoimmune POF model mice, whereas high expression was observed in control mice and those treated with BSJPP(moderate and high doses)and ***: BSJPP is effective in treating ZP3-induced POF in mice and the increase in the expression of BMP-15 and Cx43 may be implicated in the mechanism underpinning the action.

关键词： Chinese medical formula Primary ovarian Insufficiency Zona pellucida Follicle-stimulating hormone Luteinizing hormone Connexin 43

Highly Dispersed Pt Species with Excellent Stability and Catalytic Performance by Reducing a Perovskite-Type Oxide Precursor for CO Oxidation

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Transactions of Tianjin University 2018年第6期24卷 547-554页

作者： Chunyu Fang Huixian Zhong Ying Wei Jiaming Wang Siran zhang lihong zhang Yuan Liu Tianjin Key Laboratory of Applied Catalysis Science and Engineering School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin 300072 China

A new scheme for the preparation of highly dispersed precious metal catalysts is proposed in this work. Samples of LaCol-xPtxO3/SiO2 （x = 0.03, 0.05, 0.07, 0.09, and 0.10） were prepared through a simple method of citrate acid complexa-tion combined with impregnation. In a nanocrystallite of LaCOl-xPtxO3, ions of lanthanum, cobalt, and platinum are evenly mixed at the atomic level and confined within the nanocrystallite. In the reduction process, platinum ions were reduced and migrated onto the surface of the nanocrystallite, and the platinum should be highly dispersed owing to the even mixing of the platinum ions in the precursor. When x = 0.05 or lower, the highest dispersion of Pt could be achieved. The highly dispersed Pt is stable, because of the strong interaction between Pt atoms and the support. The catalysts were characterized by BET surface area, temperature-programmed reduction, X-ray diffraction, transmission electron microscopy, CO temperature-programmed desorption, and turnover frequency. Compared with general precious metal Pt catalysts, the LaCo0.95Pt0.05O3/ SiO2 catalyst exhibited better activity for CO oxidation, and it maintained stability at a high temperature of 400 ℃ for 250 h with complete CO conversion.

关键词： High dispersion Perovskite-type oxide Platinum Carbon monoxide Catalytic oxidation

All-optical temporal fractional order differentiator using an in-fiber ellipsoidal air-microcavity

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Journal of Semiconductors 2017年第12期38卷 81-84页

作者： lihong zhang Shuqian Sun Ming Li Ninghua Zhu State Key Laboratory of Integrated Optoelectronics Institute of SemiconductorsChinese Academy of Sciences School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of Sciences

An all-optical temporal fractional order differentiator with ultrabroad bandwidth （-1.6 THz） and extremely simple fabrication is proposed and experimentally demonstrated based on an in-fiber ellipsoidal air-microcavity. The ellipsoidal air-microcavity is fabricated by splicing a single mode fiber （SMF） and a photonic crystal fiber （PCF） together using a simple arc-discharging technology. By changing the arc-discharging times, the propagation loss can be adjusted and then the differentiation order is tuned. A nearly Gaussian-like optical pulse with 3 dB bandwidth of 8 nm is launched into the differentiator and a 0.65 order differentiation of the input pulse is achieved with a processing error of 2.55%.

关键词： optical signal processing optical differentiator in-fiber ellipsoidal air-microcavity

Dehydrogenation of isobutane to isobutene over a Pt-Cu bimetallic catalyst in the presence of LaAlO_(3) perovskite

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Chinese Journal of Chemical Engineering 2021年第4期34卷 203-211页

作者： Yanyong Li Meng Ge Jiameng Wang Mengquan Guo Fanji Liu Mingxun Han Yanhong Xu lihong zhang Department of Catalysis Science and Technology Tianjin Key Laboratory of Applied Catalysis Science&TechnologySchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China Department of Materials Engineering Xuzhou College of Industrial TechnologyXuzhou 221140China

In this study,isobutane dehydrogenation to isobutene reaction was carried out in a series of PtCu bimetallic catalysts prepared by coimpregnation *** catalysts were characterized by means of several techniques,including XRD,N_(2) adsorptiondesorption,TEM,XPS,H2TPR and *** results show that the existence of LaAlO_(3) perovskite can enhance the dispersion and sintering resistance of metal nanoparticles and facilitate the transfer of carbon deposits from active sites to the ***,the perovskite nanoparticles can also inhibit the reduction of CuOx and the formation of PtCu alloys,resulting in the suitable interaction between Pt and *** PtCu/LaAlO_(3)/SiO_(2)catalyst exhibits the optimal dehydrogenation performance with an isobutane conversion of 47%and isobutene selectivity of 92%after 310 min reaction,which was ascribed to the unique role of LaAlO_(3) perovskite as well as the appropriate PtCu interaction.

关键词： Isobutane dehydrogenation Catalyst Nanoparticles Silica LaAlO_(3)perovskite Pt-Cu interaction

THE EXISTENCE AND BLOW-UP OF THE RADIAL SOLUTIONS OF A(k_(1),k_(2))-HESSIAN SYSTEM INVOLVING A NONLINEAR OPERATOR AND GRADIENT

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Acta Mathematica Scientia 2022年第4期42卷 1414-1426页

作者： Guotao WANG Zedong YANG Jiafa XU lihong zhang School of Mathematics and Computer Science Shanxi Normal UniversityTaiyuan 030031China School of Mathematical Sciences Chongqing Normal UniversityChongqing 401331China

In this paper,we are concerned with the existence of the positive bounded and blow-up radial solutions of the(k1,k2)-Hessian system■where G is a nonlinear operator,Ki=Ski(λ(D^(2) z_(i)))+ψ_(i)(|x|)|▽_(zi)|^(ki),i=1,*** the appropriate conditions on gi and g2,our main results are obtained by using the monotone iterative method and the Arzela-Ascoli ***,our main results also extend the previous existence results for both the single equation and systems.

关键词： (k_(1),k_(2))-Hessian system nonlinear operator blow-up monotone iterative method gradient