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Implementation experience of a 12-month intervention to introduce intermittent kangaroo mother care to eight Chinese neonatal intensive care units

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World Journal of Pediatrics 2022年第12期18卷 849-853页

作者： Xin liu xiao-Hui Chen Zhan-Kui li Bei Cao Shao-Jie Yue Qiong-Yu liu Chuan-Zhong Yang Chang-yi Yang ying-Xi Zhao Geng-li Zhao Qi Feng Neonatal Intensive Care Unit Department of PediatricsPeking University First HospitalBeijing 100034China Department of Neonatology Nanjing Maternity and Child Health Care HospitalNanjingChina Department of Neonatology Northwest Women’s and Children’s HospitalXi’anChina Department of Neonatology The Maternal and Child Health Care Hospital of Hunan ProvinceChangshaChina Department of Neonatology Xiangya Hospital Central South UniversityChangshaChina Department of Neonatology Women&Children’s Health Care Hospital of LinyiLinyiChina Department of Neonatology Shenzhen Maternity&Child Healthcare HospitalShenzhenChina Department of Neonatology Fujian Provincial Maternity and Children’s HospitalFuzhouChina Nuffield Department of Medicine University of OxfordOxfordUK Department of Obstetrics and Gynecology Peking University First HospitalBeijingChina

Kangaroo mother care(KMC)is recommended by the World Health Organization for the care of preterm and low-birth-weight *** has been shown to increase survival rates and the quality of life of preterm and low-birth-weight infants,including improved clinical outcomes,weight gain and thermoregulation when compared to conventional care[1,2,3].More recent research focused on KMC in high-risk preterm,critically ill newborns and newborns requiring special care,which suggested that KMC helped to stabilize the vital signs of preterm infants[4,5].KMC is well accepted and promoted by medical associations and professional organizations around the world[6,7].In November 2015 with support from the National Health Commission of China,participants from ten hospitals based in different areas of China received theoretical and practical training on *** a four-year period,health professionals from these hospitals participated in theoretical and practical training,which included two operation training from foreign experts,two academic lectures,and three study tours to hospitals in the UK,Sweden and the *** this period,the KMC Operational Manual for Premature Infants in China was developed,and a 12-month prospective multicenter study of KMC for preterm infants was conducted in the eight *** the present study,we further examine whether KMC was sustained as a practice during a 12-month period from April 2018 to March 2019 and the characteristics of preterm infants that received KMC.

关键词： mother sustained promoted

Using machine learning algorithms to estimate stand volume growth of Larix and Quercus forests based on national-scale Forest Inventory data in China

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Forest Ecosystems 2022年第3期9卷 396-406页

作者： Huiling Tian Jianhua Zhu xiao He Xinyun Chen Zunji Jian Chenyu li Qiangxin Ou Qi li Guosheng Huang Changfu liu Wenfa xiao Ecology and Nature Conservation Institute Chinese Academy of ForestryKey Laboratory of Forest Ecology and Environment of National Forestry and Grassland AdministrationBeijing100091China Co-Innovation Center for Sustainable Forestry in Southern China Nanjing Forestry UniversityNanjing210037China Institute of Forest Resource Information Techniques Chinese Academy of ForestryKey Laboratory of Forest Management and Growth ModelingNational Forestry and Grassland AdministrationBeijing100091China Academy of Forest Inventory and Planning National Forestry and Grassland AdministrationBeijing100714China School of Forestry and Landscape Architecture Anhui Agricultural UniversityHefei230036AnhuiChina

Estimating the volume growth of forest ecosystems accurately is important for understanding carbon sequestration and achieving carbon neutrality ***,the key environmental factors affecting volume growth differ across various scales and plant functional *** study was,therefore,conducted to estimate the volume growth of Larix and Quercus forests based on national-scale forestry inventory data in China and its influencing factors using random forest *** results showed that the model performances of volume growth in natural forests(R^(2)=0.65 for Larix and 0.66 for Quercus,respectively)were better than those in planted forests(R^(2)=0.44 for Larix and 0.40 for Quercus,respectively).In both natural and planted forests,the stand age showed a strong relative importance for volume growth(8.6%–66.2%),while the edaphic and climatic variables had a limited relative importance(linear increase in planted Quercus *** the specific locations(i.e.,altitude and aspect)of sampling plots exhibited high relative importance for volume growth in planted forests(4.1%–18.2%).Altitude positively affected volume growth in planted Larix forests but controlled volume growth negatively in planted Quercus ***,the effects of other environmental factors on volume growth also differed in both stand origins(planted versus natural)and plant functional types(Larix versus Quercus).These results highlighted that the stand age was the most important predictor for volume growth and there were diverse effects of environmental factors on volume growth among stand origins and plant functional *** findings will provide a good framework for site-specific recommendations regarding the management practices necessary to maintain the volume growth in China's forest ecosystems.

关键词： Stand volume growth Stand origin Plant functional type National forest inventory data Random forest algorithms

Tempering stability of Fe–Cr–Mo–W–V hot forging die steels

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International Journal of Minerals,Metallurgy and Materials 2017年第10期24卷 1145-1157页

作者： Yuan-ji Shi xiao-chun Wu Jun-wan li Na Min School of Materials Science and Engineering Shanghai University Shanghai 200072 China

The tempering stability of three Fe–Cr–Mo–W–V hot forging die steels(DM, H21, and H13) was investigated through hardness measurements and transmission electron microscopy(TEM) observations. Both dilatometer tests and TEM observations revealed that DM steel has a higher tempering stability than H21 and H13 steels because of its substantial amount of M_2C(M represents metallic element) carbide precipitations. The activation energies of the M_2C carbide precipitation processes in DM, H21, and H13 steels are 236.4, 212.0, and 228.9 kJ/mol, respectively. Furthermore, the results indicated that vanadium atoms both increase the activation energy and affect the evolution of M_2C carbides, resulting in gradual dissolution rather than over-aging during tempering.

关键词： tempering stability hot forging die steels carbide precipitation

Sensing properties and mechanisms of LaF_(3)-Co_(3)O_(4) nanorods for low-concentration methanol detection

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Rare Metals 2024年第5期43卷 2193-2204页

作者： xiao-Xi He Hong-Feng Chai yi-Wen Zhou Ke-Wei liu Ze-Xin Yu Chao Zhang College of Mechanical Engineering Yangzhou UniversityYangzhou225127China Institutefor Manufacturing Technologies of Ceramic Components and Composites(IMTCCC) University of Stuttgart70569 StuttgartGermany

Methanol is one of the characteristic gases that distinguish between healthy individuals and lung cancer(LC)lesions in exhaled human *** concentration in exhaled breath is generally below one part per million(1×10^(-6)).The second-phase composite is widely regarded as one of the methods to improve the gas-sensing perfor-mance of metal oxide semiconductor(MOS)*** this study,LaF_(3)-Co_(3)O_(4) was synthesized by a simple hydrothermal method to enhance its low-concentration methanol gas-sensing performance.5 at%LaF_(3)-Co_(3)O_(4) nanorods exhibited excellent methanol detection performance,including a wider linear detection concentration range(0.2×10^(-6)~5×10^(-6)),a response value exceeding 4.0 for 1×10^(-6)methanol at 275°C and 75%relative humidity(RH),long-term stability(maximum deviation within 15%over 2 weeks),and excellent *** mechanism of performance enhancement was studied using various techniques,and density functional *** special spinel structure of Co_(3)O_(4),the high ionic migration of F-in LaF_(3),the larger specific surface area of 5 at%LaF_(3)-Co_(3)O_(4) nanorods,and the generated crystal defects all explain the excellentmethanol gas-sensing *** work provides a novel route to prepare MOS composite materials for low-concentration methanol gas detection.

关键词： Gas sensor LaF_(3) Co_(3)O_(4) Methanol Lung cancer

Growth mechanism of palladium clusters on rutile TiO_2 (110) surface

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Journal of Natural Gas Chemistry 2012年第5期21卷 544-555页

作者： Weina Zhao Huaxiang lin yi li Yongfan Zhang Xin Huang Wenkai Chen Department of Chemistry Fuzhou UniversityFuzhou 350116FujianChina Fujian Provincial Key Laboratory of Photocatalysis-State Key Laboratory Breeding Base Fuzhou UniversityFuzhou 350002FujianChina

Oxide-supported transition metal systems have been the subject of enormous interest due to the improvement of catalytic properties relative to the separate *** in this paper,we embark on a systematic study for Pd n （n=1-5） clusters adsorbed on TiO2 （110） surface based on DFT-GGA calculations utilizing periodic supercell models.A single Pd adatom on the defect-free surface prefers to adsorb at a hollow site bridging a protruded oxygen and a five-fold titanium atom along the [110] direction,while Pd dimer is located on the channels with the Pd-Pd bond parallel to the *** to the transition states （TSs） search,the adsorbed Pd trimer tends to triangular growth mode,rather than linear mode,while the Pd4 and Pd5 clusters prefer three-dimensional （3D） ***,the oxygen vacancy has almost no influence on the promotion of Pd n cluster ***,of particular significance is that the Pd-TiO2 interaction is the main driving force at the beginning of Pd nucleation,whereas the Pd-Pd interaction gets down to control the growth process of Pd cluster as the cluster gets *** is hoped that our theoretical study would shed light on further designing high-performance TiO2 supported Pd-based catalysts.

关键词： density functional theory TiO2 (110) surface palladium cluster adsorption

Broadband absorption performance of 3D-printed polyetheretherketone-based electromagnetic wave-absorbing composites

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Chinese Journal of Aeronautics 2024年第8期37卷 547-558页

作者： lin BAI Nan CHANG Meiying ZHAO Chi HOU yi CAO Dichen li School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Chengdu Aircraft Design and Research Institute Chengdu 610091China Xi’an Key Laboratory of Advanced Structure Design and Application of Aircraft Northwestern Polytechnical UniversityXi’an 710072China State Key Laboratory for Manufacturing System Engineering Xi’an Jiaotong UniversityXi’an 710054China

The rapid development of additive manufacturing technology has offered a new avenue for designing and fabricating high wave-absorbing meta *** this study,the mechanical properties and broadband absorption performance of Poly-Ether-Ether-Ketone(PEEK)–based electromagnetic wave–absorbing composite materials was *** high-performance polymer PEEK was used as the matrix,and the materials with electromagnetic wave loss,such as reduced graphene oxide,Carbonyl Iron(CI),and Flake CI(FCI),were used as *** on the theory of impedance matching,a wave-absorbing structure with a gradual impedance gradient was designed and *** test results showed that at the 2.0–18.0 GHz frequency band,the coverage rate of the effective absorption bandwidth was up to 72.0%,the average optimal reflectivity was–18.09 dB,and the wide-angle absorption range was 0°–30°.The advantages of additive manufacturing technology in designing and fabricating wave-absorbing structures are presented,demonstrating that the technology is an effective method for creating broadband absorbing structures.

关键词： Absorption performance Additive manufacturing Electromagnetic absorption PEEK composite materials Gradual structure Broadband absorption

An Adaptive Nonhydrostatic Atmospheric Dynamical Core Using a Multi-Moment Constrained Finite Volume Method

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Advances in Atmospheric Sciences 2022年第3期39卷 487-501页

作者： Pei HUANG Chungang CHEN Xingliang li Xueshun SHEN Feng xiao State Key Laboratory for Strength and Vibration of Mechanical Structures Xi’an Jiaotong UniversityXi’an 710049China Center of Numerical Weather Prediction China Meteorological AdministrationBeijing 100081China Department of Mechanical Engineering Tokyo Institute of TechnologyTokyo 226-8502Japan

An adaptive 2 D nonhydrostatic dynamical core is proposed by using the multi-moment constrained finite-volume(MCV) scheme and the Berger-Oliger adaptive mesh refinement(AMR) algorithm. The MCV scheme takes several pointwise values within each computational cell as the predicted variables to build high-order schemes based on single-cell reconstruction. Two types of moments, such as the volume-integrated average(VIA) and point value(PV), are defined as constraint conditions to derive the updating formulations of the unknowns, and the constraint condition on VIA guarantees the rigorous conservation of the proposed model. In this study, the MCV scheme is implemented on a height-based, terrainfollowing grid with variable resolution to solve the nonhydrostatic governing equations of atmospheric dynamics. The AMR grid of Berger-Oliger consists of several groups of blocks with different resolutions, where the MCV model developed on a fixed structured mesh can be used directly. Numerical formulations are designed to implement the coarsefine interpolation and the flux correction for properly exchanging the solution information among different blocks. Widely used benchmark tests are carried out to evaluate the proposed model. The numerical experiments on uniform and AMR grids indicate that the adaptive model has promising potential for improving computational efficiency without losing accuracy.

关键词： adaptive mesh refinement multi-moment constrained finite-volume method nonhydrostatic model dynamical core high-order methods

Continuous morphing trailing-edge wing concept based on multi-stable nanomaterial

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Chinese Journal of Aeronautics 2021年第7期34卷 219-231页

作者： Fengqian HAO Tao TANG Yuan GAO yimeng li Shenghui yi Jian LU Department of Mechanical Engineering City University of Hong KongHong Kong 999077China Centre for Advanced Structural Materials City University of Hong Kong Shenzhen Research InstituteGreater Bay Joint DivisionShenyang National Laboratory for Materials ScienceShenzhen 518057China Beijing Thm Technology Co. Ltd.Beijing 100084China

Morphing technology is one of the most effective methods to improve the flight efficiency of *** control surfaces based morphing method is mature and widely used on current civil and military aircraft,but insufficiently effective for the entire flight *** research on morphing wing still faces the challenge that the skin material for morphing should be both deformable and *** this study,a continuous morphing trailing-edge wing with a new multi-stable nano skin material fabricated using surface mechanical attrition treatment technology was proposed and *** fluid dynamics simulation was used to study the aerodynamic performance of the continuous morphing trailing-edge *** show that the lift coefficient increases with the increase of deflection angle and so does the lift-drag ratio at a small angle of *** importantly,compared with the wing using flaps,the continuous morphing trailing-edge wing can reduce drag during the morphing process and its overall aerodynamic performance is improved at a large angle of attack *** field analysis reveals that the continuous morphing method can delay flow separation in some situations.

关键词： Aerodynamic performance Computational fluid dynamics Continuous morphing trailing-edge wing Multi-stable nanomaterial Surface mechanical attrition treatment

Deep decalcification of factory-provided freezing acidolysis solution to achieveα-high-strength gypsum

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Chinese Journal of Chemical Engineering 2024年第5期69卷 143-151页

作者： Wencai Ye Yulu li Yonggang Dong lin Yang Yun yi Jianxin Cao School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China Engineering Research Center of Efficient Utilization for Industrial Waste Guizhou UniversityGuiyang 550025China Key Laboratory of Guizhou Province for Green Chemical Industry and Clean Energy Technology Guizhou UniversityGuiyang 550025China

The freezing acidolysis solution of the nitric acid-phosphate fertilizer process has a high calcium content,which makes it difficult to produce fine phosphate and high water-soluble phosphate fertilizer ***,based on the potential crystallization principle of calcium sulfate in NH_(4)NO_(3)-H_(3)PO_(4)-H_(2)O,the deep decalcification(*** removal)technology to achieveα-high-strength gypsum originated from freezing acidolysis-solutions has been firstly proposed and ***,calcium can be removed from the factory-provided freezing acidolysis-solution by neutralizing it with ammonia,followed by the addition of ammonium sulfate *** a result,the formation of calcium sulfate in the reaction system undergoes the nucleation and growth of CaSO_(4)·2H_(2)O(DH),as well as its dissolution and crystallization into short columnarα-CaSO_(4)·0.5H_(2)O(α-HH).Remarkably,with the molar ratio of SO_(4)^(2-)/Ca^(2+)at 1.8,the degree of neutralization(NH_(3)/HNO_(3) molar ratio)at 1.7,the reaction temperature of 94℃,and the reaction time of 300 min,the decalcification rate can reach 86.89%,of which the high-strengthα-CaSO_(4)·0.5H_(2)O(α-HH)will be ***,the deep decalcification product meets the standards for the production of fine phosphates and highly water-soluble phosphate ***,the 2 h flexural strength ofα-HH is 5.3 MPa and the dry compressive strength is 36.8 MPa,which is up to the standard of commercialα-HH.

关键词： Nitrophosphate Ammonia neutralization Deep decalcification High-strengthα-hemihydrate gypsum Controlled crystallization at atmospheric pressure