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Energy consumption of electrooxidation systems with boron-doped diamond electrodes in the pulse current mode

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International Journal of Minerals,Metallurgy and Materials 2013年第1期20卷 106-112页

作者： Jun-jun Wei Xu-hui Gao li-fu Hei Jawaid Askari cheng-ming li Institute of Advanced Materials and Technology University of Science and Technology Beijing Institute of Manufacturing Engineering National University of Sciences & Technology (NUST)

A pulse current technique was conducted in a boron-doped diamond （BDD） anode system for electrochemical waste- water treatment. Due to the strong generation and weak absorption of hydroxyl radicals on the diamond surface, the BDD elec- trode possesses a powerful capability of electrochemical oxidation of organic compounds, especially in the pulse current mode. The influences of pulse current parameters such as current density, pulse duty cycle, and frequency were investigated in terms of chemical oxygen demand （COD） removal, average current efficiency, and specific energy consumption. The results demon- strated that the relatively high COD removal and low specific energy consumption were obtained simultaneously only if the current density or pulse duty cycle was adjusted to a reasonable value. Increasing the frequency slightly enhanced the COD re- moval and average current efficiency. A pulse-BDD anode system showed a stronger energy saving ability than a constant-BDD anode system when the electrochemical oxidation of phenol of the two systems was compared. The results prove that the pulse current technique is more cost-effective and more suitable for a BDD anode system for real wastewater treatment. A kinetic analysis was presented to explain the above results.

关键词： diamond fihlls boron doping electrochemical oxidation hydroxyl radicals energy consumption wastewater treat- ment

Development and Evaluation of a PCR Kit for Authentication of Panax quinquefolius *** PCR-Restriction Fragment Length Polymorphism

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Journal of Analysis and Testing 2022年第4期6卷 424-430页

作者： Xue-Song Wang li-Mei liu li-Yuan Sun ming-cheng li School of Laboratory Medicine College of Medical TechnologyBeihua UniversityJilin132013China Innovation Center for Detection Technology on DNA Fingerprint of Traditional Chinese Medicine Jilin ProvinceJilin132013China

Panax quinquefolius L.(American ginseng)and Panax ginseng *** are famous herbal *** authentication of the species has grown to be a significant *** study aims to develop a PCR kit for the authentication of Panax quinquefolius *** Panax ginseng based on the nuclear internal transcribed spacer 2(ITS2)gene with the improved PCR-restriction fragment length polymorphism(PCR-RFLP)*** reagent components in the development work were prepared and determined by the kit consisting of the DNA extraction,PCR amplification,and restriction enzyme digestion systems.A total of 21 batches of Panax quinquefolius *** Panax ginseng samples collected from different areas were *** specificity,stability,and repeatability were *** purity of genomic DNA extracted was 1.73±0.13 according to the ratio of A_(260)/A_(280),and the mass concentration was 3.15±0.22μg/g(using the kit).PCR amplicons of Panax quinquefolius *** Panax ginseng were 122 bp in *** the PCR products were digested by restriction enzyme Hinf I,a distinct pattern exhibited in the species of Panax quinquefolius *** two fragments of 40 bp and 80 bp respectively,whereas those from Panax ginseng in addition to adulterated samples could *** confirmed that the DNA kit results were stable and repeatable after 10,15,and 20 freeze-thaw cycles:the evaluation was 100%*** DNA kit proposed in the study can be used for the identification of Panax quinquefolius L.

关键词： Panax quinquefolius L. Authentication Nuclear internal transcribed spacer 2 PCR

Functions and Application of the AP2/ERF Transcription Factor Family in Crop Improvement

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Journal of Integrative Plant Biology 2011年第7期53卷 570-585页

作者： Zhao-Shi Xu ming Chen lian-cheng li You-Zhi Ma National Key Facility of Crop Gene Resources and Genetic Improvement (NFCRI) Key Laboratory of Crop Genetics and Breeding Ministry of Agriculture Institute of Crop Science Chinese Academy of Agriculture Sciences (CAAS) Beijing 100081 China

Plants have acquired sophisticated stress response systems to adapt to changing environments. It is important to understand plants＇ stress response mechanisms in the effort to improve crop productivity under stressful conditions. The AP2/ERF transcription factors are known to regulate diverse processes of plant development and stress responses. In this study, the molecular characteristics and biological functions of AP2/ERFs in a variety of plant species were analyzed. AP2/ERFs, especially those in DREB and ERF subfamilies, are ideal candidates for crop improvement because their overexpression enhances tolerances to drought, salt, freezing, as well as resistances to multiple diseases in the transgenic plants. The comprehensive analysis of physiological functions is useful in elucidating the biological roles of AP2/ERF family genes in gene interaction, pathway regulation, and defense response under stress environments, which should provide new opportunities for the crop tolerance engineering.

关键词： AP2/ERF gene regulation signal pathway stress tolerance transgenic plant

Discussion of thermodynamic features within the PNJL model

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Chinese Physics C 2018年第12期42卷 32-43页

作者： Jin-li Zhang cheng-ming li Hong-Shi Zong Department of Physics Nanjing UniversityNanjing 210093China Joint Center for Particle Nuclear Physics and CosmologyNanjing 210093China 2.State Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsCASBeijing 100190China

We discuss some thermodynamical features of a QCD system within the two-flavor Polyakov loop ex- tended Nambu Jona-Lasinio （PNJL） model. Several thermodynamical quantities of interest （pressure, energy density, specific heat, speed of sound, etc.） are investigated and discussed in detail with two different forms of Polyakov loop potential. The effective coupling strength G incorporating a quark feedback （quark condensate） through operator product expansion is also discussed, as well as the relationship between color deconfinement and chiral phase crossover. We find that some thermodynamical quantities have quite different behavior for different Polyakov loop potentials. By changing the characteristic temperature To of the pure Yang-Mills feld, we find that when To becomes small, color deconfinement might happen earlier than chiral phase crossover, while their relationship can be determined via some thermodynamical quantities. Furthermore, the behavior of the thermodynamical quantities is quite different in the two different forms of Polyakov loop potential studied. Especially, one of the potentials, specific heat, has two peaks, which correspond to color deconfinement and chiral phase crossover respectively. This interesting phenomenon may shed some light on whether the inflection points at the same temperature or not for lattice QCD and of the chiral condensate and deconfinement transitions happen experimental studies.

关键词： deconfinement specific heat transition temperature

Deposition of crackless freestanding diamond films on Mo substrates with Zr interlayer

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 246-250页

作者： Zheng liu cheng-ming li liang-xian Chen li-mei Wang li-fu Hei Fan-xiu Lu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The Mo substrate with Zr interlayer,namely composite substrate,was employed to solve the problem of crack formation in the freestanding diamond film *** diamond films deposited on the composite substrates by the direct current arc plasma jet chemical vapor deposition（CVD） method were investigated with scanning electron microscopy（SEM）,X-ray photoelectron spectroscopy （XPS）,X-ray diffraction（XRD）,and Raman *** addition,the stress distribution during the large area freestanding diamond film deposition on the composite substrate was analyzed based on the finite element model *** results reveal that Zr interlayer can be easily destroyed during the post-deposition cooling process,which is helpful for stress release and crack avoiding in diamond films.

关键词： chemical vapor deposition diamond film interlayer thermal stress finite element analysis

Optical characterization of single-crystal diamond grown by DC arc plasma jet CVD

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International Journal of Minerals,Metallurgy and Materials 2017年第12期24卷 1424-1430页

作者： li-fu Hei Yun Zhao Jun-jun Wei Jin-long liu cheng-ming li Fan-xiu Lü Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China

Optical centers of single-crystal diamond grown by DC arc plasma jet chemical vapor deposition(CVD) were examined using a low-temperature photoluminescence(PL) technique. The results show that most of the nitrogen-vacancy(NV) complexes are present as NV-centers, although some H2 and H3 centers and B-aggregates are also present in the single-crystal diamond because of nitrogen aggregation resulting from high N_2 incorporation and the high mobility of vacancies under growth temperatures of 950–1000°C. Furthermore, emissions of radiation-induced defects were also detected at 389, 467.5, 550, and 588.6 nm in the PL spectra. The reason for the formation of these radiation-induced defects is not clear. Although a Ni-based alloy was used during the diamond growth, Ni-related emissions were not detected in the PL spectra. In addition, the silicon-vacancy(Si-V)-related emission line at 737 nm, which has been observed in the spectra of many previously reported microwave plasma chemical vapor deposition(MPCVD) synthetic diamonds, was absent in the PL spectra of the single-crystal diamond prepared in this work. The high density of NV-centers, along with the absence of Ni-related defects and Si-V centers, makes the single-crystal diamond grown by DC arc plasma jet CVD a promising material for applications in quantum computing.

关键词： diamond single crystals direct current arc plasma jet chemical vapor deposition photoluminescence optical spectra

A New Alkaloid from Sinomenium acutum

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Chinese Chemical Letters 2005年第11期16卷 1481-1483页

作者： Wei ming cheng Feng QIU li Jun WU Xin Sheng YAO Department of Natural Products Chemistry Shenyang Pharmaceutical University Shenyang 110016

Sinomenium acutum is widely used in East and South Asia for the treatment of many diseases, especially rheumatoid arthritis （RA）. The chemical research on Sinomenium acutum led to the isolation of a new alkaloid compound （1）. On the basis of chemical evidences and spectral analysis, 1 was identified as N-（1, 7-dimethoxylphenanthren-2-yl）acetamide.

关键词： Sinomenium acutum alkaloid N-(l 7-dimethoxylphenanthren-2-yl)acetamide.

Nonextensive effects on QCD chiral phase transition with a chiral chemical potential

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Chinese Physics C 2022年第10期46卷 98-106页

作者： Ya-Peng Zhao Shu-Yu Zuo cheng-ming li School of Mathematics and Physics Henan Urban Construction UniversityPingdingshan 467036China College of Science Henan University of TechnologyZhengzhou 450000China School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China

In this study,we investigate the QCD chiral phase diagram in the presence of a chiral chemical potential μ based on nonextensive statistical mechanics.A feature of this new statistic is a dimensionless nonextensivity parameter q,which summarizes all possible effects violating the assumptions of Boltzmann-Gibbs(BG)statistics(when q→1,it returns to the BG case).Within the nonextensive Polyakov-Nambu-Jona-Lasinio model,we find that as μ increases,the critical end point(CEP)in the T-μ plane continues to CEP_(5)in the T-μ plane,and nonextensive effects have a significant impact on the evolution from the CEP to CEP_(5).Generally,with an increase in q,both the CEP and CEP_(5)move in the direction of a lower temperature T and larger chemical potentialμ(μ_(5)).In addition,we find that chiral charge density ngenerally increases with T,μ,μ_(5),and *** study may provide useful hints about lattice QCD and relativistic heavy-ion collision experiments.

关键词： nonextensive statistics Polyakov-Nambu-Jona-Lasinio model QCD phase diagram chiral chemical potential

QCD chiral phase transition and critical exponents within the nonextensive Polyakov-Nambu-Jona-Lasinio model

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Chinese Physics C 2021年第7期45卷 65-73页

作者： Ya-Peng Zhao Shu-Yu Zuo cheng-ming li Collage of Physics and Electrical Engineering Anyang Normal UniversityAnyang 455000China College of Science Henan University of TechnologyZhengzhou 450000China School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China

We present a nonextensive version of the Polyakov-Nambu-Jona-Lasinio model that is based on nonextentive statistical *** new statistics model is characterized by a dimensionless nonextensivity parameter q that accounts for all possible effects violating the assumptions of the Boltzmann-Gibbs(BG) statistics(for q→ 1,it returns to the BG case).Based on the nonextensive Polyakov-Nambu-Jona-Lasinio model,we discussed the influence of nonextensive effects on the curvature of the phase diagram at μ=0 and especially on the location of the critical end point(CEP).A new and interesting phenomenon we found is that with an increase in q,the CEP position initially shifts toward the direction of larger chemical potential and lower ***,when q is larger than a critical value qc,the CEP position moves in the opposite *** other words,as q increases,the CEP position moves in the direction of smaller chemical potential and higher *** U-turn phenomenon may be important for the search of CEP in relativistic heavy-ion collisions,in which the validity of BG statistics is questionable due to strong fluctuations and long-range correlations,and nonextensive effects begin to manifest *** addition,we calculated the influence of the nonextensive effects on the critical exponents and found that they remain almost constant with q.

关键词： nonextensive statistics Polyakov-Nambu-Jona-Lasinio model QCD chiral phase