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Factors involved in the success of Castanea henryi stem cuttings in different cutting mediums and cutting selection periods

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Journal of Forestry Research 2021年第4期32卷 1627-1639页

作者： Wangzun Chen libing he Shiyi Tian Joseph Masabni Huan Xiong Feng Zou Deyi Yuan Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees Ministry of EducationCentral South University of Forestry and TechnologyChangsha 410004People’s Republic of China Texas A&M AgriLife Center at Dallas 17360 Coit RdDallasTX 75252USA

Chinquapin(Castanea henryi) is a dual-purpose tree species in China valued for as a source of timber and *** investigated the effect of four cutting mediums(pure vermiculite;peat:river sand at 3:1 v/v;peat:krasnozem at 1:1 v/v;and pure krasnozem) and three stem cutting periods(March,May,and July) on rooting performance of *** *** cutting periods and cutting mediums greatly influenced the rooting rate of ***,ranging from 3.35 to 77.31%.Principal component analysis indicated that the best combination of cutting period and cutting medium was semi-hardwood cuttings(May cuttings)+*** evidence indicated that adventitious root initials were present by week 5-6,and that the site of root primordia initiation was observed in the vascular *** anatomical structures observed at different periods indicated that a xylem/radius ratio of29.90-37.42% and a fractured phloem fiber ring are indicative of rooting *** relational model between rooting index and medium properties indicated that nutrient content and porosity significantly influenced callus ***,pH strongly affected *** root formation,with the Pearson correlation coefficients for May and July cuttings of-0.856 and-0.947,*** protocol is helpful to achieve mass clone propagation of improved *** genotypes,thus overcoming a common hurdle in chinquapin breeding programs.

关键词： Adventitious roots formation Castane henryi Medium pH Phloem fiber ring Xylem

3D printing of bone tissue engineering scaffolds

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Bioactive Materials 2020年第1期5卷 82-91页

作者： Chong Wang Wei Huang Yu Zhou libing he Zhi he Ziling Chen Xiao he Shuo Tian Jiaming Liao Bingheng Lu Yen Wei Min Wang School of Mechanical Engineering Dongguan University of TechnologySongshan LakeDongguanGuangdongPR China Department of Orthopaedics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubeiPR China Department of Mechanical Engineering The University of Hong KongPokfulam RoadHong KongHong Kong SARPR China Department of Chemistry Tsinghua UniversityBeijingPR China Institute of Biomedical and health engineering Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdongPR China

Tissue engineering is promising in realizing successful treatments of human body tissue loss that current methods cannot treat well or achieve satisfactory clinical *** scaffold-based bone tissue engineering,a high performance scaffold underpins the success of a bone tissue engineering strategy and a major direction in the field is to produce bone tissue engineering scaffolds with desirable shape,structural,physical,chemical and biological features for enhanced biological performance and for regenerating complex bone ***-dimensional(3D)printing can produce customized scaffolds that are highly desirable for bone tissue *** enormous interest in 3D printing and 3D printed objects by the science,engineering and medical communities has led to various developments of the 3D printing technology and wide investigations of 3D printed products in many industries,including biomedical engineering,over the past *** is now possible to create novel bone tissue engineering scaffolds with customized shape,architecture,favorable macro-micro structure,wettability,mechanical strength and cellular *** article provides a concise review of recent advances in the R&D of 3D printing of bone tissue engineering *** also presents our philosophy and research in the designing and fabrication of bone tissue engineering scaffolds through 3D printing.

关键词： 3D printing Bone tissue engineering Scaffold Bioceramic Polyester Hydrogel Biomolecule Controlled release

Patterning single-layer materials by electrical breakdown using atomic force microscopy

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Nanotechnology and Precision Engineering 2024年第1期7卷 71-77页

作者： Yajie Yang Jiajia Lu Yanbo Xie libing Duan School of Physical Science and Technology Northwestern Polytechnical UniversityXi’an 710072China School of Aeronautics and Institute of Extreme Mechanics Northwestern Polytechnical UniversityXi’an 710072China

The development of nanoelectronics and nanotechnologies has been boosted signiﬁcantly by the emergence of 2D materials because of their atomic thickness and peculiar properties,and developing a universal,precise patterning technology for single-layer 2D materials is critical for assembling *** here is a nanomachining technique using electrical breakdown by an AFM tip to fabricate nanopores,nanostrips,and other nanostructures on *** can be achieved by voltage scanning or applying a constant voltage while moving the *** measuring the electrical current,the formation process on single-layer materials was shown *** present results provide evidence of successful pattern fabrication on single-layer MoS2,boron nitride,and graphene,although further conﬁrmation is still *** proposed method holds promise as a general nanomachining technology for the future.

关键词： 2D material Nanopattern AFM Electrical breakdown Lithography

GS-orthogonalization OMP method for space target detection via bistatic space-based radar

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Chinese Journal of Aeronautics 2024年第7期37卷 333-351页

作者： Shuyu ZheNG libing JIANG Qingwei YANG Yingjian ZHAO Zhuang WANG National Key Laboratory of Science and Technology on Automatic Target Recognition College of Electronic Science and TechnologyNational University of Defense TechnologyChangsha 410073China

A space-based bistatic radar system composed of two space-based radars as the transmitter and the receiver respectively has a wider surveillance region and a better early warning capability for high-speed targets,and it can detect focused space targets more flexibly than the monostatic radar system or the ground-based radar ***,the target echo signal is more difficult to process due to the high-speed motion of both space-based radars and space *** be specific,it will encounter the problems of Range Cell Migration(RCM)and Doppler Frequency Migration(DFM),which degrade the long-time coherent integration performance for target detection and localization *** solve this problem,a novel target detection method based on an improved Gram Schmidt(GS)-orthogonalization Orthogonal Matching Pursuit(OMP)algorithm is proposed in this ***,the echo model for bistatic space-based radar is constructed and the conditions for RCM and DFM are ***,the proposed GS-orthogonalization OMP method is applied to estimate the equivalent motion parameters of space ***,the RCM and DFM are corrected by the compensation function correlated with the estimated motion ***,coherent integration can be achieved by performing the Fast Fourier Transform(FFT)operation along the slow time direction on compensated echo *** simulations and real raw data results validate that the proposed GS-orthogonalization OMP algorithm achieves better motion parameter estimation performance and higher detection probability for space targets detection.

关键词： Bistatic space-based radar High-speed maneuvering space targets detection Range Cell Migration(RCM) Doppler Frequency Migration(DFM) Gram Schmidt(GS)-orthogonalization Orthogonal Matching Pursuit(OMP)algorithm

Staring-imaging satellite pointing estimation based on sequential ISAR images

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Chinese Journal of Aeronautics 2024年第8期37卷 261-276页

作者： Canyu WANG libing JIANG Weijun ZHONG Xiaoyuan REN Zhuang WANG National Key Laboratory of Automatic Target Recognition National University of Defense TechnologyChangsha 410073China Xi’an Satellite Control Center Xi’an 710600China

Pointing estimation for spacecraft using Inverse Synthetic Aperture Radar(ISAR)images plays a significant role in space situational awareness and ***,feature extraction and cross-range scaling of ISAR images create bottlenecks that limit performances of current estimation ***,the emergence of staring imaging satellites,characterized by complex kinematic behaviors,presents a novel challenge to this *** address these issues,this article proposes a pointing estimation method based on Convolutional Neural Networks(CNNs)and a numerical optimization algorithm.A satellite’s main axis,which is extracted from ISAR images by a proposed Semantic Axis Region Regression Net(SARRN),is chosen for investigation in this article due to its unique ***,considering the kinematic characteristic of the staring satellite,an ISAR imaging model is established to bridge the target pointing and the extracted *** on the imaging model,pointing estimation and cross-range scaling can be described as a maximum likelihood estimation problem,and an iterative optimization algorithm modified by using the strategy of random sampling-consistency check and weighted least squares is proposed to solve this ***,the pointing of targets and the cross-range scaling factors of ISAR images are *** experiments based on actual satellite orbital parameters verify the effectiveness of the proposed *** work can improve the performance of satellite reconnaissance warning,while accurate cross-range scaling can provide a basis for subsequent data processes such as 3D reconstruction and attitude estimation.

关键词： Staring-imaging Agile satellite Inverse Synthetic Aperture Radar(ISAR) Pointing estimation Cross-range scaling

A semi-infinite beam theoretical model on predicting rock slope subsidence induced by underground mining

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Journal of Mountain Science 2024年第2期21卷 633-647页

作者： LIU Xinrong WANG Nanyun ZHONG Zuliang DU libing LIANG Erwei School of Civil Engineering Chongqing UniversityChongqing 400045China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing 400044China Key Laboratory of New Technology for Construction of Cities in Mountain Area of Ministry of Education Chongqing 400045China School of Geoscience and Technology Southwest Petroleum UniversityChengdu 610500China

When the mining goaf is close to the cliff,rock slope subsidence induced by underground mining is significantly affected by its boundary *** this study,an analytical method is proposed by considering the key strata as a semi-infinite Euler-Bernoulli beam rested on a Winkler foundation with a local subsidence *** analytical solutions of deflection are derived by analyzing the boundary and continuity conditions of the ***,the analytical solutions are verified by the results from experimental tests,FEM and InSAR,*** that,the influence of changing parameters on deflections is studied with sensitivity *** results show that the distance between goaf and cliff significantly affects the deflection of semi-infinite *** response of semi-infinite beam is obviously determined by the length of goaf and the bending stiffness of *** comparisons between semi-infinite beam and infinite beam illustrate the ascendancy of the improved model in such problems.

关键词： Key strata Mining rock slope Winkler foundation Euler-Bernoulli beam Subsidence prediction

Effects of Enclosure on Grassland Ecological and Economic Benefits in Northern China

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Chinese Geographical Science 2024年第1期34卷 67-78页

作者： HU Bo WEN Qingke XI Fengjiang LI Mengyao WANG libing REN Yuejuan Aerospace Information Research Institute Chinese Academy of SciencesBeijing100094China University of Chinese Academy of Sciences Beijing100049China Inner Mongolia Remote Sensing Center Co. Ltd.Huhhot010000China Xilinhot the Maodeng pasture Xilinhot026000China China University of Mining and Technology Xuzhou221116China Shanxi Provincial Key Lab of Resources Environment and Disaster MonitoringCoal Geological Geophysical Exploration Surveying&Mapping Institute of Shanxi ProvinceJinzhong030600China

Grasslands in northern China serve the country as both an ecological barrier and a livestock production ***,installing enclosures has been becoming the major grassland restoration measure adopted by many local ***,the effects of restoration on both ecological and production benefits of grassland remain unclear for implemented grassland restoration ***,a representative rangeland in northern China,the Maodeng pasture in Inner Mongolia Autonomous Region was selected as the study area,and remote sensing monitoring analyses were carried out to quantify the ecological benefits and economic benefits from 2015 to *** results showed that:1) in terms of ecological benefits,the grassland area with a grassland coverage rate of more than 60% accounts for 32.3% of the regional area,and 86.4% of its grassland grew significantly better than the same period in2015,showing a significant improvement in grassland *** the average amount of carbon per unit area as the ecological benefit evaluation index,it increased by 27.1% to 32.48Tg C/yr from 2015 to 2021.2) In terms of economic benefits,both theoretical grass production and livestock carrying capacity increased from 2015 to *** to 2015,the theoretical grass production in 2021 increased by 24.8% to 71 900 *** livestock carrying capacity reached 52 100 sheep units in 2021,nearly 11 000 sheep units more than that in *** the study period,multiple economic indicators(on a per capita basis of permanent residents) for the pastoral area of Xilinhot City to which the Maodeng pasture belongs,have grown *** capita total income rose from 29 630 yuan(RMB) in2015 to 62 859 yuan(RMB) in *** on grassland resources to develop the pastoral ecology also broadens the potential economic development ***,the establishment of the reserve and the experiment of implanting an enclosure policy have had a significant and positive impact on Maodeng pasture’s develo

关键词： enclosure grassland ecological benefit economic benefit Maodeng pasture Inner Mongolia northern China

Identification and Expression Profile of a Neuropeptide LFRFamide-Like Gene During Different Stages of Gonadal Development in the Cephalopod Sepia pharaonis

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Journal of Ocean University of China 2024年第2期23卷 499-508页

作者： QIU Jiayin SUN Lianlian LI Shuang ZHOU Xu CHI Changfeng ZheNG libing National and Provincial Joint Engineering Research Center for Marine Germplasm Resources Exploration and Utilization School of Marine Science and TechnologyZhejiang Ocean UniversityZhoushan 316022China

Neuropeptides are widely distributed in vertebrates and invertebrates,regulating a variety of physiological activities in the organisms,such as metabolism,feeding and *** this study,to explore the function of neuropeptide LFRFamide in Sepia pharaonis,the full-length cDNA of LFRFamide-like gene(named SpLFRFL,MG869822.1)was identified with rapid amplification of cDNA ends(RACE)*** sequence of SpLFRFL was 860 bp in length and encoded 188 amino acids containing 4 different mature peptides:1 copy of PHTPFRFamide,NSLFRFamide,TIFRFamide,and 3 copies of *** alignment and phylogenetic analysis results showed that SpLFRFL shared high identity with LFRFamides of Sepia officinalis and Sepiella japonica and had the closest relationship with *** quantitative Real-time PCR(qRT-PCR),it was found that the SpLFRFL gene was highly expressed in the optic lobe and brain at three different stages during gonad development in both ***,the four mature peptides at a concentration of 0.01μmol L^(−1) could inhibit the protein synthesis in the Chinese hamster ovary cell strain-K1(CHOK1)induced by *** data suggest that SpLFRFL might be involved in the development and reproduction of *** results can contribute to future studies on neuropeptide evolution and function and benefit the cuttlefish farming.

关键词： neuropeptide LFRFamide-like cephalopod cuttlefish Sepia pharaonis development reproduction

Efficient nitrate electroreduction over Mn-doped Cu catalyst via regulating N-containing intermediates adsorption configuration

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Science China Chemistry 2024年第6期67卷 1969-1975页

作者： Limin Wu Shunhan Jia libing Zhang Ruhan Wang Jiaqi Feng Xiaofu Sun Buxing Han Beijing National Laboratory for Molecular Sciences CAS Laboratory of Colloid and Interface and ThermodynamicsCAS Research/Education Center for Excellence in Molecular SciencesCenter for Carbon Neutral ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing100049China College of Chemical Engineering and Environment China University of PetroleumBeijing102249China Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai200062China

The electrochemical reduction of NO_(3)^(-)to NH_(3)holds promise for economic and environmental benefits,presenting an energyefficient alternative to the traditional Haber-Bosch ***,challenges exist due to its sluggish kinetics,multiple intermediates,and various reaction *** this study,Mn-doped-Cu catalyst was synthesized and employed for electrochemical NO_(3)^(-)-to-NH_(3)*** doping of Mn into Cu resulted in exceptional performance,achieving a FE of 95.8%and an NH_(3)yield rate of 0.91 mol g^(-1)h^(-1)at-0.6 V in a neutral electrolyte at low NO_(3)^(-)*** experimental studies and theoretical calculations revealed that the Mn dopant enhanced the kinetic rate of NO_(2)~--to-NH_(3)and induced a distinct configuration of**** alteration decreased the energy barrier of*NO-to-*NOH,consequently promoting the conversion of NO_(3)^(-)-to-NH_(3).

关键词： nitrate reduction electrocatalysis ammonia synthesis N-intermediate green chemistry