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Insect Science 2013年第1期20卷 61-68页

作者： Xiao-yi Zhang Kai lu Jia-Liang Zhou Qiang Zhou State Key Laboratory of Biological Control and Institute of Entomology Sun Yat-sen University Guangzhou China

Nilaparvata lugens （St^il）（Hemiptera： Geometroidea）, a serious rice pest in many countries of Asia, causes a great loss in rice production every year. RNA interference （RNAi） is a powerful technology for gene fimction study in insects and a potential tool for pest control. As a core component of RNAi pathway, Dicer-2 （Dcr-2） protein determines the production of small interfering RNA （siRNA） and is crucial for the efficiency of RNAi. In this study, the full-length complementary DNA （cDNA） ofN. lugens Dcr-2 （NlDcr-2） was first cloned and analyzed, and then the RNAi experiment was conducted to explore the function ofNlDcr-2 gene. The complete Dcv-2 cDNA ofN. lugens was 4 971 bp in length with an open reading frame （ORF） of 1,656 amino acids. Phylogenetic and protein domain analysis showed that the predicted N1Dcr-2 protein was similar to Tribolium castaneum. In the RNAi experiment, the messenger RNA level of NlDcr-2 was significantly reduced by NlDcr-2 double-stranded RNA （dsRNA）（dsDcr-2）. Fifty-five per cent decrease of N1Dcr-2 was found after 4 days of unremitting feeding. No significant effect was observed on the development ofN. lugens after dsRNA ingestion.

关键词： clone Dicer-2 Nilaparvata lugens RNAi qRT-PCR

Adaptive Shape Control for Thermal Deformation of Membrane Mirror with In-plane PVDF Actuators

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Chinese Journal of Mechanical Engineering 2018年第1期31卷 187-197页

作者： yi-Fan lu Hong-Hao Yue Zong-Quan Deng Horn-Sen Tzou School of Mechatronics Engineering Harbin Institute of Technology College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics

Optical membrane mirrors are promising key components for future space telescopes. Due to their ultra-thin and high flexible properties, the surfaces of these membrane mirrors are susceptible to temperature variations. Therefore adaptive shape control of the mirror is essential to maintain the surface precision and to ensure its working performance. However, researches on modeling and control of membrane mirrors under thermal loads are sparse in open literatures. A 0.2 m diameter scale model of a polyimide membrane mirror is developed in this study. Three Polyvinylidene fluoride(PVDF) patches are laminated on the non-reflective side of the membrane mirror to serve as in-plane actuators. A new mathematical model of the piezoelectric actuated membrane mirror in multiple fields,(i.e., thermal,mechanical, and electrical field) is established, with which dynamic and static behaviors of the mirror can be analyzed.A closed-loop membrane mirror shape control system is set up and a surface shape control method based on an influence function matrix of the mirror is then investigated. Several experiments including surface displacement tracking and thermal deformation alleviation are performed. The deviations range from 15 μm to 20 μm are eliminated within 0.1 s and the residual deformation is controlled to micron level, which demonstrates the effectiveness of the proposed membrane shape control strategy and shows a satisfactory real-time performance. The proposed research provides a technological support and instruction for shape control of optical membrane mirrors.

关键词： Adaptive shape control Membrane mirror Thermal deformation PVDF Influence function matrix

An Anderson Impurity Interacting with the Helical Edge States in a Quantum Spin Hall Insulator

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Chinese Physics Letters 2018年第6期35卷 70-74页

作者： Ru Zheng Rong-Qiang He Zhong-yi lu Department of Physics Renmin University of China

Using the natural orbitals renormalization group（NORG）method,we investigate the screening of the local spin of an Anderson impurity interacting with the helical edge states in a quantum spin Hall *** is found that there is a local spin formed at the impurity site and the local spin is completel.y screened by electrons in the quantum spin Hall ***,the local spin is screened dominantly by a single active natural *** then show that the Kondo screening mechanism becomes transparent and simple in the framework of the natural orbitals *** project the active natural orbital respectively into real space and momentum space to characterize its *** conilrm the spin-momentum locking property of the edge states based on the occupancy of a Bloch state on the edge to which the impurity ***,we study the dynamical property of the active natural orbital represented by the local density of states,from which we observe the Kondo resonance peak.

关键词： An Anderson Impurity Interacting with the Helical Edge States in a Quantum Spin Hall Insulator

Highly efficient tandem Z-scheme heterojunctions for visible light-based photocatalytic oxygen evolution reaction

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Water Science and Engineering 2020年第4期13卷 299-306页

作者： yi lu Xing-kai Cui Cheng-xiao Zhao Xiao-fei Yang College of Science Nanjing Forestry UniversityNanjing 210037China School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China

Oxygen is important in maintaining a clean and reliable water *** heterojunction photocatalysts that can evolve oxygen from water splitting through an artificial Z-scheme pathway is a promising strategy for solving environmental *** this study,flower-like MoS2 nanostructures were fabricated via a simple hydrothermal process,and the electrostatic-based assembly ion-exchange method was used to construct a tandem Ag3PO4/MoS2/g-C3N4(AMC)*** as-synthesized photocatalyst exhibited significant improvements in harvesting visible light and transporting charge ***,the catalyst that was similar to the Z-scheme with intimate interface contact exhibited a strong oxygen evolution *** oxygen evolution activity of the optimal AMC-10 catalyst was approximately 11 times that of the pristine *** results indicated that addition of a small amount of the flower-like MoS2 could significantly enhance the efficiency of oxygen evolution by the *** findings in this study provide an alternative pathway for rationally designing efficient oxygen-evolving photocatalysts in order to improve the quality of water and rehabilitate the water environment.©2020 Hohai *** and hosting by Elsevier *** is an open access article under the CC BY-NC-ND license(http://***/licenses/by-nc-nd/4.0/).

关键词： Z-scheme Graphitic carbon nitride MoS2 Ag3PO4 Oxygen evolution reaction Water splitting

Fractional anisotropy of the corticospinal tract in normal adults: Preliminary study using a diffusion tensor imaging technique

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Neural Regeneration Research 2010年第3期5卷 232-235页

作者： Xuejin Sun Jihong Hu yin Mo Qing Gu yi Liu yi lu Conghui Ai Department of MRI First Affiliated Hospital of Kunming Medical College Kunming 650032 Yunnan Province China

BACKGROUND： The corticospinal tract is an important tract for conducting motor function. The majority of studies focus on lesions of the corticospinal tract on appearance and function, whereas observation of normal corticospinal pathways can also improve understanding of lesion outcomes. OBJECTIVE： To observe the normal adult corticospinal tract using a diffusion tensor imaging technique to analyze fractional anisotropy （FA） in different levels of the brain. DESIGN, TIME AND SETTING： Neuroimaging observation was performed in the MRI Department, First Affiliated Hospital of Kunming Medical College in China, from October 2005 to October 2008. PARTICIPANTS： A total of 30 healthy adults were selected from the Department of MRI, First Affiliated Hospital of Kunming Medical College in China, from October 2005 to October 2008, and people with nervous system symptoms and signs were excluded. METHODS： Participants with normal conventional MRI results underwent diffusion tensor imaging examination in a 1.5 T GE MRI （slice thickness 4-5 mm, slice gap 0） for gradient data acquisition from 15 directions. The scanning involved the entire brain from the inferior medulla oblongata to the inferior cranial plate. Imaging post-processing was performed to obtain FA values; a paired t-test was applied for statistical analysis. MAIN OUTCOME MEASURES： FA values of the bilateral corticospinal tract in the medulla oblongata, pons, cerebral peduncle, basal ganglia, corona radiata, and centrum semiovale. RESULTS： FA values in the medulla oblongata and centrum semiovale were similar （P 〉 0.01）. FA values of left corticospinal tract were significantly greater than the right side in the pons, cerebral peduncle, basal ganglia and corona radiata （P 〈 0.01）. CONCluSION： FA values vary by brain levels, including pons, cerebral peduncle, basal ganglia, and corona radiata. Moreover, FA values of the left corticospinal tract pathway were greater than the right side, which may relate to right handedness

关键词： corticospinal tract fractional anisotropy diffusion tensor imaging neuroimaging neural regeneration

Typhoon disaster risk zoning for China’s coastal area

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Frontiers of Earth Science 2022年第2期16卷 291-303页

作者： Jing ZHU yi lu Fumin REN John L McBRIDE Longbin YE Xiamen Key Laboratory of Straits Meteorology Xiamen Meteorological BureauXiamen 361012China Shanghai Typhoon Institute of China Meteorological Administration Shanghai 200030China State Key Laboratory of severe weather Chinese Academy of Meteorological SciencesBeijing 10081China School of Earth Science (Honorary)University of MelbourneMelbourne 3010Australia Research and Development Division(Emeritus Scientist) Bureau of MeteorologyMelbourne 3010Australia

Previous studies on typhoon disaster risk zoning in China have focused on individual provinces or small-scale areas and lack county-level *** this study,typhoon disaster risk zoning is conducted for China’s coastal area,based on data at the county *** precipitation and wind data for China and typhoon disaster and social data at the county level for China’s coastal area from 2004 to 2013,first we analyze the characteristics of typhoon disasters in China’s coastal area and then develop an intensity index of factors causing typhoon disasters and a comprehensive social vulnerability ***,by combining the two indices,we obtain a comprehensive risk index for typhoon disasters and conduct risk *** results show that the maximum intensity areas are mainly the most coastal areas of both Zhejiang and Guangdong,and parts of Hainan Island,which is similar to the distribution of typhoon *** maximum values of vulnerability in the northwest of Guangxi,parts of Fujian coastal areas and parts of the Shandong *** comprehensive risk index generally decreases from coastal areas to inland *** high-risk areas are mainly distributed over Hainan Island,south-western Guangdong,most coastal Zhejiang,the coastal areas between Zhejiang and Fujian and parts of the Shandong Peninsula.

关键词： typhoon disaster risk zoning comprehensive social vulnerability index China’s coastal area

Constructing Bi_(2)WO_(6)-decorated TiO_(2) composite films for photocathodic protection of 304 stainless steel

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Journal of Iron and Steel Research International 2021年第8期28卷 1054-1063页

作者： Ming-liang Wang Yuan Lin yi-ping lu Na Wei Ting-ju Li Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116024LiaoningChina School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590ShandongChina

Bi_(2)WO_(6) nanoplate/TiO_(2) nanowire and Bi_(2)WO_(6) nanoflower/TiO_(2) nanowire composite films were successfully prepared using a hydrothermal *** results show that the light absorption for Bi_(2)WO_(6)/TiO_(2) composite films is extended to the visible region after Bi_(2)WO_(6) nanoplates and nanoflowers are assembled onto TiO_(2) ***,Bi_(2)WO_(6) nanoflower/TiO_(2) nano wire composite film exhibits a better absorption property compared to Bi_(2)WO_(6) nanoplate/TiO_(2) nanowire film,which is mainly ascribed to the narrower bandgap of Bi_(2)WO_(6) nanoflower compared to that of Bi_(2)WO_(6) *** photocurrent density for Bi_(2)WO_(6) nanoflower/TiO_(2) nanowire and Bi_(2)WO_(6) nanoplate/TiO_(2) nanowire composite films can reach 95 and 62.5 μA cm-2,respectively,which are much higher than that obtained for a pure TiO_(2) nanowire film(25 μA cm-2).Meanwhile,under illumination,the pure TiO_(2) nanowire,Bi_(2)WO_(6) nanoplate/TiO_(2) nanowire and Bi_(2)WO_(6) nanoflower/TiO_(2) nanowire films can reduce the potential of the coupled 304 stainless steel in 3.5 wt.%NaCl solution by 299,719 and 739 mV,***,Bi_(2)WO_(6) nanoflower/TiO_(2) nanowire film is found to provide the best effective photocathodic protection for 304 stainless *** work not only provides an example of shape-dependent photocathodic protection based on Bi_(2)WO_(6) but also opens up new possibilities to design an ideal microstructure on the basis of semiconductor materials for future applications of photocathodic protection.

关键词： Photocathodic protection Composite film Bi_(2)WO_(6) TiO_(2) Stainless steel

Development of a prognostic model for one-year surgery risk in Crohn’s disease patients: A retrospective study

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World Journal of Gastroenterology 2020年第5期26卷 524-534页

作者： Jia-yin Yao yi Jiang Jia Ke yi lu Jun Hu Min Zhi Department of Gastroenterology Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor DiseasesThe Sixth Affiliated Hospital of Sun Yat-Sen UniversityGuangzhou 510655Guangdong ProvinceChina Department of Colorectal Surgery The Sixth Affiliated Hospital of Sun Yat-Sen UniversityGuangzhou 510655Guangdong ProvinceChina Department of Anesthesiology Guangzhou Hospital of Traditional Chinese MedicineGuangzhou 510130Guangdong ProvinceChina Guangdong Institute of Gastroenterology Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor DiseasesThe Sixth Affiliated Hospital of Sun Yat-Sen UniversityGuangzhou 510655Guangdong ProvinceChina

BACKGROUND Accelerated therapeutic treatment should be considered in patients with progressive Crohn’s disease(CD)to prevent complications as well as ***,screening for risk factors and predicting the need for early surgery are of great importance in clinical *** To establish a model to predict CD-related early *** This was a retrospective study collecting data from CD patients diagnosed at our inflammatory bowel disease center from January 1,2012 to December 31,*** data were randomly stratified into a training set and a testing set at a ratio of 8:*** logistic regression analysis was conducted with receiver operating characteristic curves constructed and areas under the curve *** model was further validated with calibration and discrimination estimated.A nomogram was finally *** A total of 1002 eligible patients were enrolled with a mean follow-up period of 53.54±13.10 *** total,24.25%of patients received intestinal surgery within 1 year after diagnosis due to complications or disease *** behavior(B2:OR[odds ratio]=6.693,Plusive enteral nutrition(OR=0.089,P<0.001)were identified as independent significant factors associated with early intestinal surgery.A prognostic model was established and further *** receiver operating characteristic curves and calculated areas under the curves(94.7%)confirmed an ideal predictive ability of this model with a sensitivity of 75.92%and specificity of 95.81%.A nomogram was developed to simplify the use of the predictive model in clinical *** This prognostic model can effectively predict 1-year risk of CD-related intest

关键词： Crohn’s disease Prognostic model Nomogram Early surgery Inflammatory bowel disease Retrospective study

The Potassium−Air Battery:Far from a Practical Reality?

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Accounts of Materials Research 2021年第7期2卷 515-525页

作者： Wanwan Wang yi-Chun lu Electrochemical Energy and Interfaces Laboratory Department of Mechanical and Automation EngineeringThe Chinese University of Hong KongShatinNew Territories 999077Hong Kong SARChina

CONSPECTUS:An energy storage system is the key bottleneck toward the widespread use of renewable energy and the development of electric vehicles(EVs).Alkali metal−oxygen batteries,which have higher gravimetric energy densities(3500−935 Wh kg−1)than conventional lithium−ion batteries(100−265 Wh kg−1),are considered to be one of the promising next-generation energy storage *** the past decade,Li−O2 batteries have been the center of the research effort owing to their highest energy ***,the poor reversibility,low round-trip efficiency,and limited cycle life originating from sluggish kinetic and serious parasitic chemistry induced by singlet oxygen hamper the development of Li−O2 *** the sluggish kinetics and severe parasitic reactions are closely related to the discharge product *** Li−O2 batteries,K−O2 batteries based on potassium superoxide offer an attractive theoretical energy density(935 Wh kg−1)with a significantly improved energy efficiency and lifetime compared to other alkali metal−O2 *** fast and reversible O2/KO2 single−electron reaction exhibits higher redox kinetics compared to the Li−O2 redox chemistries and removes the needs of catalysts or redox *** addition,the earth abundant K greatly alleviates the global shortage and uneven regional distribution of *** unique advantages of the K−O2 system make it a promising candidate for low-cost and large-scale energy ***,the development of a K−O2 battery is still in its early stages and its round-trip efficiency is still lower than that of lithium−ion *** improvement in energy efficiency and cycle life of the K−O2 batteries is crucial prior to practical *** present Account combines our efforts and other representative works on fundamental understandings and design strategies toward next-generation K−O2 *** are offered on oxygen electrode reversibility and stability,anode stabilization and alternat

关键词： battery Battery electrolyte

Thermodynamically Revealing the Essence of Order and Disorder Structures in Layered Cathode Materials

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Chinese Journal of Structural Chemistry 2019年第12期38卷 2020-2026页

作者： ZHENG Ze WENG Mou-yi YANG lu-yi HU Zong-Xiang CHEN Zhe-Feng PAN Feng School of Advanced Materials Shenzhen Graduate SchoolPeking University

Layered transition metal(TM) oxides are one of the most widely used cathode materials in lithium-ion batteries. The atomic configuration in TM layer of these materials is often known to be random when multiple TM elements co-exist in the layer(e.g. Ni, Co and Mn). By contrast, the configuration tends to be ordered if the elements are Li and Mn. Here, by using special quasi-random structures(SQS) algorithm, the essential reasons of the ordering in a promising Li-rich Mn-based cathode material Li2MnO3 are investigated. The difference of internal energy and entropy between ordered and disordered materials is calculated. As a result, based on the Gibbs free energy, it is found that Li2MnO3 should have an ordered structure in TM layer. In comparison, structures with Ni-Mn ratio of 2:1 are predicted to have a disordered TM layer, because the entropy terms have larger impact on the structural ordering than internal energy terms.

关键词： entropy special quasi-random structures(SQS) layered cathode materials Gibbs free energy