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Chinese Journal of Natural Medicines 2017年第6期15卷 417-426页

作者： DUAN bao-Zhong fang Hai-Lan LI Xi-Wen HUANG Lin-fang WANG ping CHEN Shi-Lin College of Pharmaceutical Sciences Hubei University of Chinese Medicine Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences College of Pharmaceutical Sciences Dali University Institute of Medicinal Plant Development Chinese Academy of Medical Sciences & Peking Union Medical College

The adulteration of herbal products is a threat to consumer safety. In the present study, we surveyed the species composition of commercial Radix Clerodendri Japonicum products using DNA barcoding as a supervisory method. A reference database for plant-material DNA-barcode was successfully constructed with 48 voucher samples from 12 Clerodendrum species. The database was used to identify 27 Radix Clerodendri Japonicum decoction piece samples purchased from drug stores and hospitals. The DNA sequencing results revealed that only 1 decoction piece(3.70%) was authentic C. japonicum, as recorded in the Dai Pharmacopeia, whereas the other samples were all adulterants, indicating a potential safety issue. The results indicate that decoction pieces that are available in the market have complex origins and that DNA barcoding is a suitable tool for regulation of Dai medicines.

关键词： Dai medicine DNA barcode Radix Clerodendri Japonicum Adulterants ITS 2

Source and Control of Nitrogen for X70 Pipeline Steel

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Journal of Iron and Steel Research International 2016年第7期23卷 647-654页

作者： Min WANG Yan-ping bao State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The effects of some key factors on nitrogen absorption during the smelting process of X70 pipeline steel were studied,and the source of nitrogen pick-up was analyzed to find the bottleneck for nitrogen control.A series of measures were put forward to decrease the nitrogen *** results indicated that an exponential relationship existed between the nitrogen absorption index and the free oxygen in molten *** absorption index could decrease below 0.3when free oxygen in molten steel was above 100×10^（-6） after *** low sulfur killed steel,the nitrogen absorption ratio and sulfur content satisfied a linear relationship with a slope *** free-oxygen and sulfur were beneficial to the deep desulfurization during vacuum *** contradiction of high desulfurization ratio and low nitrogen pick-up during LF process could be resolved by skimming oxidizing slag after tapping and making new high basicity top *** optimization,the average content of nitrogen in final product decreased from 46×10（-6）to 35×10（-6）.

关键词： nitrogen control nitrogen absorption surface activity element X70 pipeline steel

Mn evaporation and denitrification behaviors of molten Mn steel in the vacuum refining with slag process

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International Journal of Minerals,Metallurgy and Materials 2021年第8期28卷 1288-1297页

作者： Jian-hua Chu Yan-ping bao State Key Lab of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

Considering the precise composition control on the vacuum refining of high-Mn steel, the behaviors of both Mn evaporation and nitrogen removal from molten Mn steel were investigated via vacuum slag refining in a vacuum induction furnace. It was found that the reaction interfaces of denitrification and Mn evaporation tend to migrate from the surface of slag layer to the surface of molten steel with the gradual exposure of molten steel during the vacuum slag refining process. Significantly, compared with the experimental group without slag addition, the addition of slag into steel can result in a lower Mn evaporation rate constant of 0.0192 cm·min~(-1) at 370 Pa, while the denitrification rate is almost not affected. Besides, the slag has a stronger inhibitory effect on Mn evaporation than the reduced vacuum pressure. Moreover, the inhibitory effect of the slag layer on Mn evaporation can be weakened with the increase of the initial Mn content in molten steel. The slag layer can work as an inhibitory layer to reduce the Mn evaporation from molten steel, the evaporation reaction of Mn mainly proceeds on the surface of the molten steel. This may be attributed to the Mn mass transfer coefficient for one of reaction at steel/slag interface, mass transfer in molten slag, and evaporation reaction at slag/gas interface is lower than that of evaporation reaction at steel/gas interface. The introduction of slag is proposed for both denitrification and manganese control during the vacuum refining process of Mn steels.

关键词： manganese evaporation denitrification vacuum slag evaporation rate

Superballistic wavepacket spreading in double kicked rotor

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Science China(Physics,Mechanics & Astronomy) 2016年第8期59卷 9-15页

作者： ping fang Jiao Wang Department of Physics and Institute of Theoretical Physics and Astrophysics Xiamen University

We investigate possible ways in which a quantum wavepacket spreads. We show that in a general class of double kicked rotor system, a wavepacket may undergo superballistic spreading; i.e., its variance increases as the cubic of time. The conditions for the observed superballistic spreading and two related characteristic time scales are studied. Our results suggest that the symmetry of the studied model and whether it is a Kolmogorov-Arnold-Moser system are crucial to its wavepacket spreading behavior. Our study also sheds new light on the exponential wavepacket spreading phenomenon previously observed in the double kicked rotor system.

关键词： quantum chaos quantum transport matter waves semiclassical methods

In vitro regeneration of Populus tomentosa from petioles

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Journal of Forestry Research 2017年第3期28卷 465-471页

作者： fang Wei fang-fang Zhao bao-ming Tian School of Life Sciences Zhengzhou University

A reliable in vitro regeneration procedure for Populus tomentosa is a prerequisite for its trait improvement through genetic transformation. We established a systematic protocol for indirect regeneration of P. tomentosa using in vitro petioles of Chinese poplar cultivar ＇fasta-3＇. A high frequency of callus induction （〉97 %） was obtained from isolated petioles cultured on the modified 1/2MS basal medium supplemented with 0.5 mg/L ZT and 1.0 mg/L NAA, and the tested calli were subsequently plated on 1/2MS basal medium supplemented with 0.25 mg/L BA, 0.25 mg/L ZT, 0.25 mg/L NAA, 0.01 mg/L TDZ, and 0.5 mg/L KT for efficient regeneration of shoots after being cultured for 6 weeks. The regenerated shoots were vigorously rooted on the tested media supplemented with 1.0 mg/ L IBA and 0.5 mg/L NAA. These results can facilitate genetic transformation of P. tomentosa for trait improvements in future.

关键词： Callus induction Genetic transformation In vitro regeneration Petiole Populus tomentosa

Interfacial Zn2+-solvation regulator towards reversible and stable Zn anode

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Journal of Energy Chemistry 2025年第1期100卷 684-692页

作者： Miao Zhou Xiongbin Luo Hang Li Shan Guo Zhuang Tong Xiaotao Zhou Xu Li Zhaohui Hou Shuquan Liang Guozhao fang College of Mechanical Engineering Key Laboratory of Hunan Province for Advanced Carbon-based Functional Materials Hunan Institute of Science and Technology School of Materials Science and Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South University College of Materials and Metallurgy Guizhou University National Energy Metal Resources and New Materials Key Laboratory Central South University

Aqueous zinc-ion batteries （AZIBs） are fundamentally challenged by the instability of the electrode/electrolyte interface,predominantly due to irreversible zinc （Zn） deposition and hydrogen ***,the intricate mechanisms behind the electrochemical discrepancies induced by interfacial Zn2+-solvation and deposition behavior demand comprehensive *** molecules endowed with special functional groups （such as hydroxyl,carboxyl,etc.） have the potential to significantly optimize the solvation structure of Zn2+and regulate the interfacial electric double layer （EDL）.By increasing nucleation overpotential and decreasing interfacial free energy,these functional groups facilitate a lower critical nucleation radius,thereby forming an asymptotic nucleation model to promote uniform Zn ***,this study presents a pioneering approach by introducing trace amounts of n-butanol as solvation regulators to engineer the homogenized Zn （H-Zn） anode with a uniform and dense *** interfacial reaction and structure evolution are explored by in/ex-situ experimental techniques,indicating that the H-Zn anode exhibits dendrite-free growth,no by-products,and weak hydrogen evolution,in sharp contrast to the bare ***,the H-Zn anode achieves a remarkable Zn utilization rate of approximately 20% and simultaneously sustains a prolonged cycle life exceeding 500 ***,the H-Zn//NH4V4O10（NVO） full battery showcases exceptional cycle stability,retaining 95.04%capacity retention after 400 cycles at a large current density of 5 A *** study enlightens solvation-regulated additives to develop Zn anode with superior utilization efficiency and extended operational lifespan.

关键词： Aqueous zinc-ion batteries Interfacial reaction Asymptotic nucleation model Reversible and stable Zn anode

Low/distortion on Exterior Surface of Auto Body and Its Correction Method

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Chinese Journal of Mechanical Engineering 2012年第2期25卷 299-305页

作者： HU ping bao Jingru ZHAO Kunmin School of Automotive Engineering Dalian University of TechnologyDalian 116024China

Surface low/distortion is one of the most challenging surface deflections that have a great effect on the exterior appearance of *** studies on surface distortion/deflection have focused on evaluation and visualization techniques,the research work on correction or prevention of surface low/distortion is limited,and there is no perfect surface low/distortion corrective method that can satisfy the needs of the engineering.A B-spline based geometry morphing algorithm is proposed and then a new program based on UG-NX platform is developed to modify the die face in the surface low/distortion *** verify this developed system,the experimental dies that can replicate the surface low/distortion phenomenon successfully is put to *** geometric variables are introduced to describe the basic geometry of typical depression features of automotive outer *** experimental dies are then designed to reflect various combinations of these geometric *** stamping experiments are conducted on cold rolled grade 5（CR5） sheet steel and various static measurements,such as oil-stoning,laser scanner,etc,are performed to measure and record the surface low/*** approaches including good bearing,holds in blank and die face morphing that aim to correct low/distortions are tried out and surface low/distortions are observed in the specimen with reverse draw depth of 10 *** measurement results show that die morphing is a practical and effective method to correct the surface low/*** correction method proposed can be used to minimize the occurrence of surface low/distortion in die manufacturing,which has certain reference significance to the correction of surface low/distortion.

关键词： sheet metal forming surface low/distortion surface deflection corrective method morphing algorithm

Progressive failure analysis of slope with strain-softening behaviour based on strength reduction method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第2期14卷 101-109页

作者： Ke ZHANG ping CAO Rui bao School of Resources and Safety Engineering Central South University Kuming Prospecting Design Institute of China Nonferrous Metals Industry

Based on the strength reduction method and strain-softening model,a method for progressive failure analysis of strain-softening slopes was presented in this *** mutation is more pronounced in strain-softening analysis,and the mutation of displacement at slope crest was taken as critical failure *** engineering example was provided to demonstrate the validity of the present *** method was applied to a cut slope in an industry *** results are as follows:(1) The factor of safety and the critical slip surface obtained by the present method are between those by peak and residual *** analysis with peak strength would lead to non-conservative results,but that with residual strength tends to be overly conservative.(2) The thickness of the shear zone considering strain-softening behaviour is narrower than that with non-softening analysis.(3) The failure of slope is the process of the initiation,propagation and connection of potential failure *** strength parameters are mobilized to a non-uniform degree while progressive failure occurs in the slope.(4) The factor of safety increases with the increase of residual shear strain threshold and elastic *** failure mode of slope changes from shallow slip to deep ***'s ratio and dilation angle have little effect on the results.

关键词： Shear strength reduction Strain-softening Peak strength Residual strength Progressive failure analysis

A Tensor Neural Network with Layerwise Pretraining： Towards Effective Answer Retrieval

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Journal of Computer Science & Technology 2016年第6期31卷 1151-1160页

作者： Xin-Qi bao Yun-fang Wu Key Laboratory of Computational Linguistics Peking University Beijing 100871 China

In this paper we address the answer retrieval problem in community-based question answering. To fully capture the interactions between question-answer pairs, we propose an original tensor neural network to model the relevance between them. The question and candidate answers are separately embedded into different latent semantic spaces, and a 3-way tensor is then utilized to model the interactions between latent semantics. To initialize the network layers properly, we propose a novel algorithm called denoising tensor autoencoder （DTAE）, and then implement a layerwise pretraining strategy using denoising autoencoders （DAE） on word embedding layers and DTAE on the tensor layer. The experimental results show that our tensor neural network outperforms various baselines with other competitive neural network methods, and our pretraining DTAE strategy improves the system＇s performance and robustness.

关键词： artificial intelligence language parsing and understanding machine learning

Changes in the food supply capacity of alpine grassland ecosystem:A dialectic synthesis of natural and anthropogenic drivers

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Advances in Climate Change Research 2020年第1期11卷 1-10页

作者： fang Yi-ping Institute of Mountain Hazards&Environment Chinese Academy of SciencesChengdu610041China College of Resource and Environment University of Chinese Academy of SciencesBeijing100049China

Grassland-based animal husbandry and livestock production is the main contributor to livelihood creation for *** using the structural dynamics method,this study quantified the changes in the food supply capacity(FSC)of alpine grassland ecosystem and sensitivity to significant *** findings indicated that:i)Natural factors were the dominated forces affecting FSC,and their contribution was 71.3%.Of these natural elements,the net primary productivity(NPP)and precipitation were the largest contributors,accounting for approximately 35%.The sensitivity index of the FSC to NPP and precipitation during grassland growing season were 4.1 and 1.9 *** the contrary,human factors like warm shed area,density of road,capacity for access to information,contributed to 28.7%of the total ***)More intense snow disaster had a larger negative impact on *** disaster can cause dramatic reduction in FSC,with a loss rate of 27.6%and with none intense disaster more negative impacts,iii)The continuing increase of FSC in the past 30 years from 1984 to 2014 was due to the significant increase of precipitation and NPP in the growing season of alpine ***,successful adaptation to climate change was critical to combat the climatic adversely impact on ***,strengthening information dissemination,road accessibility and knowledge popularization of local residents'disaster reduction should be place high priority for improving FSC。

关键词： Food supply capacity Alpine grassland ecosystem Structural dynamics method Snow disaster Permafrost