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Switchable shape memory polymer bio-inspired adhesive and its application for unmanned aerial vehicle landing

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Chinese Journal of Aeronautics 2024年第3期37卷 380-390页

作者： Qingsong HE Zefang ZHAO Qiyun ZHONG Siyuan LIU kai deng Yongqi LIU Ning ZHANG Zijie ZHAO Fengjiang ZHAN Jianfeng ZHAO Jiangsu Provincial Key Laboratory of Bionic Functional Materials College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Advanced Technology for Small and Medium-Sized UAV Ministry of Industry and Information TechnologyUnmanned Aerial Vehicles Research InstituteNanjing University of Aeronautics and AstronauticsNanjing 210016China State Key Laboratory of Mechanics and Control of Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Functional Morphology and Biomechanics Institute of ZoologyKiel UniversityKiel 24098Germany

Controlled and switchable adhesion is commonly observed in biological *** recent years,many scholars have focused on making switchable bio-inspired ***,making a bio-inspired adhesive with high adhesion performance and excellent dynamic switching properties is still a challenge.A Shape Memory Polymer Bio-inspired Adhesive(SMPBA)was successfully developed,well realizing high adhesion(about 337 kPa),relatively low preload(about90 kPa),high adhesion-to-preload ratio(about 3.74),high switching ratio(about 6.74),and easy detachment,which are attributed to the controlled modulus and contact area by regulating temperature and the Shape Memory Effect(SME).Furthermore,SMPBA exhibits adhesion strength of80–337 kPa on various surfaces(silicon,iron,and aluminum)with different roughness(Ra=0.021–10.280)because of the conformal contact,reflecting outstanding surface *** finite element analysis verifies the bending ability under different temperatures,while the adhesion model analyzes the influence of preload on contact area and ***,an Unmanned Aerial Vehicle(UAV)landing device with SMPBA was designed and manufactured to achieve UAV landing on and detaching from various *** study provides a novel switchable bio-inspired adhesive and UAV landing method.

关键词： Bio-inspired adhesive Shape memory polymers Switchable adhesive Unmanned aerial vehicle Landing

Ethanol Extract of Glycyrrhiza uralensis Fisch:Antidiarrheal Activity in Mice and Contraction Effect in Isolated Rabbit Jejunum

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Chinese Journal of Integrative Medicine 2023年第4期29卷 325-332页

作者： WEN Jing ZHANG Jian-wu LYU Yuan-xia ZHANG Hui deng kai-xi CHEN Hong-xue WEI Ying Department of Pharmacy North Sichuan Medical CollegeNanchongSichuan Province 637100China

Objective:To evaluate the antidiarrheal effect of ethanol extract of Glycyrrhiza uralensis Fisch root(GFR)in vivo and jejunal contraction in ***:In vivo,50 mice were divided into negative control,positive control(verapamil),low-,medium-and high-dose GFR(250,500,1,000 mg/kg)groups by a random number table,10 mice in each *** antidiarrheal activity was evaluated in castor oil-induced diarrhea mice model by evacuation index(El).In vitro,the effects of GFR(0.01,0.03,0.1,0.3,1,3,and 10 g/L)on the spontaneous contraction of isolated smooth muscle of rabbit jejunum and contraction of pretreated by Acetylcholine(ACh,10μmol/L)and KCl(60 mmol/L)were observed for 200 *** addition,CaCl_(2)was accumulated to further study its mechanism after pretreating jejunal smooth muscle with GFR(1 and 3 g/L)or verapamil(0.03 and 0.1μmol/L)in a Ca^(2+)-free-high-K+solution containing ethylene diamine tetraacetic acid(EDTA).Results:GFR(500 and 1,000 mg/kg)significantly reduced El in castor oil-induced diarrhea model mice(P<0.01).Meanwhile,GFR(0.01,0.03,0.1,0.3,1,3,and 10 g/L)inhibited the spontaneous contraction of rabbit jejunum(P<0.05 or P<0.01).Contraction of jejunums samples pretreated by ACh and KCI with 50% effective concentration(EC50)values was 1.05(0.71-1.24),0.34(0.29-0.41)and 0.15(0.11-0.20)g/L,*** addition,GFR moved the concentration-effect curve of CaCl_(2)down to the right,showing a similar effect to ***:GFR can effectively reduce diarrhea and inhibit intestinal contraction,and these antidiarrheal effects may be based on blocking L-type Ca^(2+) channels and muscarinic receptors.

关键词： Glycyrrhiza uralensis Fisch antidiarrheal spasmolysis Chinese medicine

Preparation of Nanometer-structured TiO_2 Thin Films by Sol-Gel Method

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Journal of Wuhan University of Technology(Materials Science) 2002年第4期17卷 51-53页

作者：何峰 School of Materials Science and Engineering Wuhan University of Technology Wuhan China

The transparent anatase TiO 2 nanometer thin films were prepared by the sol-gel method on soda-lime glass.X-ray diffraction,thermal analysis and UV-visible spectrophotometer were used to analyze the formation of the *** increasing the heat-treatment time,the average grain size has no obvious *** mechanism of grain growth in TiO 2 thin film is probably as follows:the grain of coating will become grain core later;TiO 2 sol constantly deposited on the surface of TiO 2 grain and formed membrane with increasing of coating cycle times;TiO 2 grain in the film grow steadily.

关键词： TiO 2 sol-gel method nanometer thin films

ESTIMATION OF CARRIER FREQUENCY OFFSETS FOR MIMO SYSTEMS WITH DISTRIBUTED TRANSMIT ANTENNAS

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Journal of Electronics(China) 2007年第4期24卷 455-461页

作者： deng kai Tang Youxi Lei Xia Li Shaoqian National Anti-jamming Communications Laboratory University of Electronic Science and Technology of China Chengdu 610054 China

The problem of estimating the carrier frequency offsets in Multiple-Input Multiple-Output (MIMO) systems with distributed transmit antennas is addressed. It is supposed that the transmit antennas are distributed while the receive antennas are still centralized, and the general case where both the time delays and the frequency offsets are possibly different for each transmit antenna is considered. The channel is supposed to be frequency flat, and the macroscopic fading is also taken into consideration. A carrier frequency offset estimator based on Maximum Likelihood (ML) is proposed, which can separately estimate the frequency offset for each transmit antenna and exploit the spatial diversity. The Cramer-Rao Bound (CRB) for synchronous MIMO (i.e., the time delays for each transmit antenna are all equal) is also derived. Simulation results are given to illustrate the per- formance of the estimator and compare it with the CRB. It is shown that the estimator can provide satisfactory frequency offset estimates and its performance is close to the CRB for the Signal-to-Noise Ratio (SNR) below 20dB.

关键词： Multiple-Input Multiple-Output (MIMO) Distributed antenna Carrier frequency offset estimation Maximum Likelihood (ML) Cramer-Rao Bound (CRB)

Protein requirements of early-weaned Dorper crossbred female lambs

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Journal of Integrative Agriculture 2017年第5期16卷 1138-1144页

作者： MA Tao deng kai-dong TU Yan ZHANG Nai-feng SI Bing-wen XU Gui-shan DIAO Qi-yu Feed Research Institute/Key Laboratory of Feed Biotechnology Ministry of Agriculture/Chinese Academy of Agricultural Sciences College of Animal Science Jinling Institute of Technology College of Animal Science Tarim University

The net protein （NP） and metabolizable protein （MP） requirements of Dorper crossbred female lambs from 20 to 35 kg body weight （BW） were assessed in a comparative slaughter trial. Thirty-five Dorper×thin-tailed Hart crossbred lambs weaned at approximately 50 d of age （（19.1±2.37） kg of BW） were used. Seven randomly selected lambs were slaughtered at the beginning of the trial as baseline group （BL）. An intermediate group of seven randomly selected lambs fed ad libitum （AL） intake was slaughtered when the lambs reached an average BW of 28.6 kg. The remaining 21 lambs were allotted randomly to three levels of dry matter intake： AL or restricted to 70 or 40% of the AL intake. All lambs were slaughtered when the sheep fed AL intake reached 35 kg of BW. Total body N and N retention were determined. The results showed that the maintenance requirements for NP and MP were 1.75 and 3,37 g kg^-1 metabolic shrunk body weight （SBW^0.75）, respectively. The partial efficiency of protein use for maintenance was 0.52. The NP requirements for growth ranged from 10.9 to 42.4 g d^-1 for the lambs gaining 100 to 350 g d^-1 from 20 to 35 kg BW. The partial efficiency of MP for growth was 0.52. In conclusion, the NP and MP requirements for the maintenance and growth of Dorper crossbred female lambs were lower than those reported by AFRC （1993） and NRC （2007） recommendations.

关键词： growth maintenance metabolizable protein net protein lamb

Recent advances in nutrient requirements of meat-type sheep in China:A review

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Journal of Integrative Agriculture 2022年第1期21卷 1-14页

作者： MA Tao deng kai-dong TU Yan ZHANG Nai-feng ZHAO Qi-nan LI Chang-qing JIN Hai DIAO Qi-yu Key Laboratory of Feed Biotechnology of the Ministry of Agriculture and Rural Affairs/Laboratory of Ruminant Nutrition Feed Research InstituteChinese Academy of Agricultural SciencesBeijing 100081P.R.China College of Animal Science and Food Engineering Jinling Institute of TechnologyNanjing 211100P.R.China Inner Mongolia Academy of Agriculture&Animal Husbandry Sciences Hohhot 010030P.R.China

China has the world’s largest sheep flock and the largest producer of sheep meat by far. However, the nutrient requirements have not been systemically studied and there is a lack of knowledge of nutrient requirement for meat-type sheep in *** 2008, the nutrient requirements of meat-type sheep in China has been systematically investigated. In this review, we introduced the history of studies of nutrient requirements of meat-type sheep in China, summarized the recent advances in nutrient requirements of meat-type sheep, and highlighted the future directions of researches on nutrient requirements of meat-type sheep in China.

关键词： meat-type sheep requirement energy protein mineral

The fractions of post-binary-interaction stars and evolved blue straggler stars on the red giant branch of globular clusters

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Research in Astronomy and Astrophysics 2021年第9期21卷 101-110页

作者： Dan-Dan Wei Bo Wang Hai-Liang Chen Hai-Feng Wang Xiao-Bo Gong Dong-Dong Liu deng-kai Jiang Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of ScienceKunming 650216China University of Chinese Academy of Science Beijing 100049China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China South-Western Institute for Astronomy Research Yunnan UniversityKunming 650500China LAMOST

The red giant branch(RGB)of globular clusters(GCs)is home to some exotic stars,which may provide clues on the formation of multiple stellar populations in *** is well known that binary interactions are responsible for many exotic ***,it is important to understand what fraction of stars on the RGB of GCs is the result of binary *** this paper,we performed a binary population synthesis study to track the number of post-binary-interaction(post-BI)stars that appear on the RGB,with particular emphasis on the evolved blue straggler stars(E-BSSs).Assuming an initial binary fraction of nearly 50%,we find that about half of the objects on the RGB(called giants)underwent the binary interactions,and that E-BSSs account for around 10%of the giants in our standard *** also compare the properties of post-BI giants that evolved from different *** find that the initial orbital period and mass ratio distributions significantly affect the fraction of post-BI *** results imply that the non-standard stars from binary interactions provide a non-negligible contribution to the RGB stars in GCs,which should be considered in future investigations of the origin of multiple stellar populations.

关键词： blue stragglers stars:chemically peculiar globular clusters:general binaries:general

Three new late-type hypervelocity star candidates from Gaia DR2 with refined selection criteria

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Research in Astronomy and Astrophysics 2020年第3期20卷 170-184页

作者： Jiao Li Shi Jia Yan Gao deng-kai Jiang Thomas Kupfer Ulrich Heber Chao Liu Xue-Fei Chen Zhan-Wen Han Yunnan observatories Chinese Academy of SciencesKunming 650011China Key Laboratory for the Structure and Evolution of Celestial Objects Yunnan observatoriesChinese Academy of SciencesKunming 650011China University of Chinese Academy of Sciences Beijing 100049China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacaoChina Kavli Institute for Theoretical Physics University of CaliforniaSanta BarbaraCA 93106USA Department of Physics University of CaliforniaSanta BarbaraCA 93106USA Dr.Remeis-Sternwarte&ECAP University of Erlangen-NurnbergErlangenGermany Key Lab of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

Several dozen hypervelocity star(HVS)candidates have been reported based on the second data release of Gaia(Gaia DR2).However,it has been proven that the radial velocities of some Gaia HVS candidates are not *** this paper,we employ refined astrometric criteria to re-examine Gaia DR2,arriving at a more reliable sample of HVS and high velocity star candidates than those found by previous *** develop a method called Binary Escape Probability Analysis to identify some HVS *** method allows us to work with stars having only two epochs of measured radial *** stars were usually discarded in previous similar studies.A scrutiny of our final results sheds light on selection effects present in our studies,which we propose to be the focus of future *** total,we find three late-type(2 G-type and 1 K-type)HVS and 21 high velocity star candidates,3 and 11 of which are new,*** by their historical trajectories,which we calculate,all three HVS candidates could not have had Galactic center *** monitoring is required to confirm their status.

关键词： stars kinematics and dynamics-evolution-statistics

Macromineral requirements of Dorper×thin-tailed Han crossbred female lambs

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Journal of Integrative Agriculture 2015年第8期14卷 1617-1626页

作者： JI Shou-kun XU Gui-shan DIAO Qi-yu deng kai-dong JIANG Cheng-gang TU Yan ZHANG Nai-feng Feed Research Institute Chinese Academy of Agricultural Sciences College of Animal Science Tarim University College of Animal Science Jinling Institute of Technology

A comparative slaughter trial was conducted to determine the net mineral requirements for maintenance and growth of Dorper crossbred female lambs raised from 20 to 35 kg of body weight（BW）.Thirty-five Dorper×thin-tailed Han crossbred female lambs of（20.3±1.14） kg BW were used： 7 lambs were randomly chosen and slaughtered at the beginning of the experiment as the baseline group for measuring the initial body composition; another 7 lambs were randomly chosen and offered a pelleted mixed diet ad libitum and slaughtered at（27.0±0.73） kg BW; the remaining 21 lambs were randomly divided into 3 groups of 7 animals each and subjected to the same diet either ad l ibitum or at 70 or 40% of ad libitum *** 21 lambs were fed in 7 slaughter groups, with each group consisting of one lamb from each treatment（ad libitum, 70 or 40% of ad libitum intake）.The 3 groups were slaughtered when the sheep fed ad libitum attained（33.8±0.52） kg of *** body composition of five minerals（Ca, P, Na, K, and Mg） was *** net mineral requirements for maintenance were 35.01, 25.18, 9.30, 31.35, and 2.03 mg kg–1 empty BW（EBW） for Ca, P, Na, K, and Mg, respectively, and the net growth requirement per kg of EBW gain ranged from 9.73 to 8.87 g of Ca, 5.83 to 5.27 g of P, 1.73 to 1.63 g of Na, 3.73 to 4.08 g of K, and 0.26 to 0.25 g of Mg for Dorper crossbred lambs in China, *** estimates of mineral requirements with Dorper crossbred lambs in the current study were not consistent with the recommendations from previous studies.

关键词： macrominerals comparative slaughter trials maintenance requirements growth requirements sheep