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Chinese Journal of Aeronautics 2024年第8期37卷 404-420页

作者： Yuqing QIU Yan LI Jinxi lang Yuxian LIU Zhong WANG School of Automation Northwestern Polytechnical UniversityXi’an 710129China

As the elevator and rudder can be used actively for control,in addition to the rotors,Coaxial High-speed Helicopters(CHHs)have the problems of control redundancy and changing control authority in the transition *** paper presents a robust-augmentation transitioning flight control design for a CHH under the adverse conditions of parametric uncertainties and external ***,based on control characteristic analysis,an Adaptive Filtered Nonlinear Dynamic Inversion(AFNDI)controller is proposed for the angular rate to handle the effect of unknown unstructured uncertainties and external *** analysis proves that the presented angular rate controller can guarantee steady-state and transient ***,the attitude angle and velocity controllers are also ***,an Incremental-based Nonlinear Prioritizing Control Allocation(INPCA)method is designed to take into account control surface transition and changing control authority,which efficiently distributes the required moments between coaxial rotors and aero-surfaces,and avoids the control reversal problem of the yaw *** the proposed control architecture,the low-pass filter is introduced to alleviate the adverse influence of time delay and measurement ***,the effectiveness of the proposed controller is demonstrated through nonlinear numerical simulations,and is compared with existing *** results show that the proposed control law can improve both capabilities of disturbance rejection and fast response,and works satisfactorily for the CHH transitioning control characteristic.

关键词： Coaxial high-speed helicopter Transition mode Attitude control Control allocation Robust adaptive control

Zr-doped titanium lithium ion sieve and EP-granulated composite:Superb adsorption and recycling performance

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Particuology 2022年第10期20卷 100-110页

作者： Suyu Zhou Xiaojing Guo Xi Yan Yan Chen Wanzhong lang The Education Ministry Key Laboratory of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional MaterialsDepartment of Chemistry and Chemical EngineeringShanghai Normal UniversityShanghai 200234China

Lithium ion sieve(LIS)has attracted great attention due to its high adsorption selectivity towards Li+.Herein,a new type of Zr-doped Ti-LIS(HZrTO)was synthesized by a simple calcination *** adsorption capacity increased from 56.3 mgg-1(before doping)to 93.2 mgg-1 after doping in LiOH solution(lithium 1.8gL-1).The adsorption isotherm and adsorption kinetics of HZrTO accord with the langmuir isotherm and the pseudo-second-order kinetic equation,*** experiments showed that HZrTO has good stability and *** addition,HZrTO was granulated via epoxy resin(E-12),and the obtained granular adsorbent showed good adsorption capacity,excellent stability and high selectivity towards Li+.

关键词： Lithium ion sieve Lithium titanium oxide Zr-doped Granulation

Improving in vivo Uranyl Removal Efficacy of a Nano-Metal Organic Framework by Interior Functionalization with 3-Hydroxy-2-pyridinone

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Chinese Journal of Chemistry 2022年第17期40卷 2054-2060页

作者： Mengping Chen lang lang Lei Chen Xiaomei Wang Cen Shi Qiwen Sun Yigong Xu Juan Diwu Shuao Wang State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences(RAD-X)and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education InstitutionsSoochow UniversitySuzhouJiangsu215123 China

The environmental contamination of uranium will occur in scenarios such as nuclear accidents and leakage from nuclear waste storage sites,which eventually leads to the internal uranium exposure of people,causing consequential injuries of renal failure,osteosarcoma,*** development of uranyl specific chelating agents that could sequester uranium in vivo is in urgent need and is important for the safe and efficient development of nuclear *** organic frameworks(MOFs)already serve as efficient uranium depletion materials in solutions of a wide range of pH and ionic strength for nuclear fuel recycling,uranium extraction from seawater,as well as environmental ***,a chromium-based nano-metal organic framework(nano-MOF)functionalized interiorly with 3,2-HOPO ligands,MIL-101-HOPO,is rationally *** vitro adsorption experiments show that MIL-101-HOPO exhibits high adsorption selectivity and fast adsorption kinetics for *** results of in vivo uranyl decorporation assays reveal that MIL-101-HOPO with the decoration of HOPO ligands on the interior wall exhibits significantly increased uranyl removal ratio in kidneys comparing to the pristine nMOFs,and is more effective than the clinically used ZnNa_(3)-*** those results corroborate the interior functionalization of MOFs as an efficient strategy to develop promising uranyl decorporation agents.

关键词： Metal-organic frameworks Uranium 3,2-HOPO Adsorption Sequestration

Endoscopic and surgical resection of T1a/T1b esophageal neoplasms: A systematic review

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World Journal of Gastroenterology 2013年第9期19卷 1424-1437页

作者： George Sgourakis Ines Gockel Hauke lang Department of General and Abdominal Surgery Johannes Gutenberg University Hospital of Mainz 2nd Surgical Department and Surgical Oncology Unit of "Korgialenio-Benakio" Red Cross Hospital of Athens

AIM: To investigate potential therapeutic recommendations for endoscopic and surgical resection of T1a/ T1b esophageal neoplasms. METHODS: A thorough search of electronic databases MEDLINE, Embase, Pubmed and Cochrane Library, from 1997 up to January 2011 was performed. An analysis was carried out, pooling the effects of outcomes of 4241 patients enrolled in 80 retrospective studies. For comparisons across studies, each reporting on only one endoscopic method, we used a random effects meta-regression of the log-odds of the outcome of treatment in each study. "Neural networks" as a data mining technique was employed in order to establish a prediction model of lymph node status in superficial submucosal esophageal carcinoma. Another data mining technique, the "feature selection and root cause analysis", was used to identify the most impor-tant predictors of local recurrence and metachronous cancer development in endoscopically resected patients, and lymph node positivity in squamous carcinoma (SCC) and adenocarcinoma (ADC) separately in surgically resected patients. RESULTS: Endoscopically resected patients: Low grade dysplasia was observed in 4% of patients, high grade dysplasia in 14.6%, carcinoma in situ in 19%, mucosal cancer in 54%, and submucosal cancer in 16% of patients. There were no significant differences between endoscopic mucosal resection and endoscopic submucosal dissection (ESD) for the following parameters: complications, patients submitted to surgery, positive margins, lymph node positivity, local recurrence and metachronous cancer. With regard to piecemeal resection, ESD performed better since the number of cases was significantly less [coefficient: -7.709438, 95%CI: (-11.03803, -4.380844), P < 0.001]; hence local recurrence rates were significantly lower [coefficient: -4.033528, 95%CI: (-6.151498, -1.915559),P < 0.01]. A higher rate of esophageal stenosis was observed following ESD [coefficient: 7.322266, 95%CI: (3.810146, 10.83439), P < 0.001]. A

关键词： Superficial esophageal cancer Endoscopic resection Mucosal infiltration Submucosal involvement Recurrent tumor Controversies in treatment Squamous cell carcinoma Adenocarcinoma Lymphatic invasion Vascular invasion Submucosal layer Superficial submucosal layer Middle third submucosal layer Deep third submucosal layer Esophageal cancer Endoscopic gastrointestinal surgical procedures Endoscopic gastrointestinal surgery Lymph node dissection Dysplasia

Tensile strength behavior of cement-stabilized dredged sediment reinforced by polypropylene fiber

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 380-392页

作者： Lei lang Jiangshan LI Xin CHEN Lijun HAN Ping WANG State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicChinese Academy of SciencesWuhan 430071China Hubei Provincial Key Laboratory of Contaminated Sludge and Soil Science and Engineering Wuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

This study evaluated the feasibility of using polypropylene fiber(PF)as reinforcement in improving tensile strength behavior of cement-stabilized dredged sediment(CDS).The effects of cement content,water content,PF content and length on the tensile strength and stress–strain behavioral evolutions were evaluated by conducting splitting tensile strength ***,the micro-mechanisms characterizing the tensile strength behavior inside PF-reinforced CDS(CPFDS)were clarified via analyzing macro failure and microstructure *** results indicate that the highest tensile strengths of 7,28,60,and 90 d CPFDS were reached at PF contents of 0.6%,1.0%,1.0%,and 1.0%,exhibiting values 5.96%,65.16%,34.10%,and 35.83%higher than those of CDS,***,3 mm,PF of showed the best reinforcement *** CPFDS exhibited obvious tensile strain-hardening characteristic,and also had better ductility than *** mix factor(C_(C)^(a)/C_(w)^(b))and time parameter(q_(t0)(t))of CDS,and the reinforcement index(k_(t-PF))of CPFDS were used to establish the tensile strength prediction models of CDS and CPFDS,considering multiple *** PF“bridge effect”and associated cementation-reinforcement coupling actions inside CPFDS were mainly responsible for tensile strength behavior *** key findings contribute to the use of CPFDS as recycled engineering soils.

关键词： dredged sediment chemical stabilization fiber reinforcement splitting tensile strength micro-mechanisms

Genome editing for horticultural crop improvement

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Horticulture Research 2019年第1期6卷 291-306页

作者： Jiemeng Xu Kai Hua Zhaobo lang Shanghai Center for Plant Stress Biology National Key Laboratory of Plant Molecular GeneticsCenter of Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai 200032China

Horticultural crops provide humans with many valuable *** improvement of the yield and quality of horticultural crops has been receiving increasing research *** the development and advantages of genome-editing technologies,research that uses genome editing to improve horticultural crops has substantially increased in recent ***,we briefly review the different genome-editing systems used in horticultural research with a focus on clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated 9(Cas9)-mediated genome *** also summarize recent progress in the application of genome editing for horticultural crop *** combination of rapidly advancing genome-editing technology with breeding will greatly increase horticultural crop production and quality.

关键词： Genome CRISPR crops

The research progress of tiling array technology and applications

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Chinese Science Bulletin 2008年第6期53卷 817-824页

作者： lang XianYu WANG Jun CHI XueBin Supercomputing Center Computer Network Information Center Chinese Academy of Sciences Beijing 100080 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Beijing Genomics Institute Chinese Academy of Sciencesl Beijing 101300 China

Tiling array technology was improved from microarray technology. Over the past five years, tiling array has become an important tool for gathering genome information. Its features of high density and high throughput allow people to probe into life from the whole-genome level. This paper is a survey of tiling array technology and its applications. In addition, some typical algorithms for identifying expressed probe signals are described and compared.

关键词：生物信息学信号识别嵌合芯片技术生物芯片

Control of Antagonistic McKibben Muscles via a Bio-inspired Approach

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Journal of Bionic Engineering 2022年第6期19卷 1771-1789页

作者： Xinyi Chen Wenxin Zhu Wenyu Liang Yilin lang Qinyuan Ren State Key Laboratory of Industrial Control Technology Zhejiang University310027HangzhouZhejiangChina Institute for Infocomm Research A^(*)STAR138632SingaporeSingapore

McKibben muscles are increasingly used in many robotic applications due to their advantages of lightweight,compliant,and skeletal muscles-like ***,there are still huge challenges in the motion control of McKibben muscles due to the system nonlinearity(e.g.,hysteresis)and model *** investigate the control issues,a soft artificial arm actuated by an antagonistic pair of McKibben muscles,mimicking the biological structure of skeleton-muscle systems,is *** by the biological motor control capability that humans can control and coordinate a group of muscles to achieve complex motions,a cerebellum-like controller based on Spiking Neural Networks(SNNs)is employed for the motion control of the developed artificial *** from the employment of the SNN-based cerebellar model,the proposed control scheme provides online adaptive learning capability,good computational efficiency,fast response,and strong ***,several simulations and experiments are conducted subject to different environmental *** simulation and experimental results verify that the proposed method can achieve good tracking performance,adaptability,and strong robustness.

关键词： McKibben muscle Cerebellum-like controller Spiking Neural Network Soft artificial arm Adaptive control

Microstructural evolution of a PM TiAl alloy during heat treatment in α+γ phase field

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Rare Metals 2012年第5期31卷 424-429页

作者： SU Meike ZHENG Lijing lang Zebao YAN Jie ZHANG Hu School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China

In this study, the effect of temperatures and cooling rates of heat treatment on the microstructure of a powder metallurgy (PM) Ti-46Al-2Cr-2Nb-(B,W) (at.%) alloy was studied. Depending on the cooling rate and temperature, the different structures were obtained from the initial near-γ (NG) microstructures by heat treatment in the α+γ field. The results show that the microstructures of samples after furnace cooling (FC) consist primarily of equiaxed γ and α 2 grains, with a few grains containing lamellae. Duplex microstructures consist mainly of γ grains and lamellar colonies were obtained in the quenching into another furnace at 900°C (QFC) samples. However, further increasing of the cooling rate to air cooling (AC) induces the transformation of α→α_2 and results in a microstructure with equiaxed γ and α_2 grains, and no lamellar colonies are found.

关键词： γ-TiAl-based alloys powder metallurgy heat treatment duplex structure phase volume fractions

Chain Extender-induced Hydrogen Bonding Organization Determines the Morphology and Properties of Thermoplastic Polycarbonate Polyurethane

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Chinese Journal of Polymer Science 2024年第1期42卷 87-96,I0009页

作者： Yi-lang Qin Ping Zhu Chen-Xi Ouyang Xia Dong Fuwai Hospital Chinese Academyof Medical Sciences&Peking Union Medical College/National Center for Cardiovascular DiseasesBejing 100037China CASKey Laboratoryof Engineering Plastics CAS Research/Education Centerfor Excellence in Molecular SciencesInstitute ofChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Thermoplastic polycarbonate polyurethanes(PCUs) are multiblock copolymers that have been applied for medical devices for long time. Aliphatic diols are common chain extenders(CE) involved in the composition of the hard segments of PCU. However, limited knowledge was discovered about how the chemical structure of CE affects the hydrogen bonding organization within PCUs and their mechanical *** investigate this problem, a group of PCUs were synthesized respectively by extending the polymer chain with 1,4-butanediol(BDO),aminoethanol(MEA), ethanediol(EO) as three kinds of chain extenders. Tiny differences in the CE chemical structure results in remarkable variations in phase separation, condensed morphologies, thermal and mechanical properties, which are characterized by Fourier transform infrared spectrometer, atomic force microscopy, small-angle X-ray scattering, differential scanning calorimetry, and tensile tests. The microstructural evolution during unilateral deformation and the different mechanism induced by the different CEs was probed and unveil by in situ wide-and small-angle X-ray diffraction. Symmetry of CE can improve the organization of the hydrogen bonding. The coherence strength of the urethane/urea group also plays a key role by comparing the two PCUs with ethanediol and aminoethanol.

关键词： Thermoplastic polycarbonate polyurethane Chain extender Hydrogen bonding Mechanical properties