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Experimental research on the launching system of auxiliary charge with filter cartridge structure

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Defence Technology（防务技术） 2024年第1期31卷 41-48页

作者： Zi-Jun chen Ze He Hong-Hao Ma Lu-qing Wang Zhao-Wu Shen CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefeiAnhui230027PR China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefeiAnhui230026PR China

A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the *** combustion chamber of the launching system is divided into two fixed chambers,one is located in the breech chamber,and the other is arranged in the *** breech chamber charge was ignited first,and the charges in the auxiliary chambers were ignited by the high-temperature,highpressure combustible gas trailing the *** this way,the combustible gas in the auxiliary chambers could compensate for the pressure drop caused by the movement of the *** proposed device features the advantage of launching a projectile with high muzzle velocity without exceeding the maximum pressure in the *** order to obtain some internal ballistic characteristics of the launch system,some critical structure,such as the length of the filter cartridge auxiliary charge,the combustion degree of the propellant in the chamber,and the length of the barrel,are *** experimental results show that with the increased auxiliary charge length,a pressure plateau or even a secondary peak pressure can be formed,which is less than the peak *** projectile velocity increased by 23.57%,14.64%,and 7.65%when the diaphragm thickness was 0 mm,1 mm,and2 mm,*** muzzle velocity of the projectile can be increased by 13.42%by increasing the length of the *** the same charge condition,with the increase of barrel length,the energy utilization rate of propellant increases by 28.64%.

关键词： Interior ballistics Charge structures Launch system Charge design

A Low Cost, Green Sustainable and Biodegradable Biomass-based Fluorine-free Water and Oil Repellent

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Chinese Journal of Polymer Science 2024年第4期42卷 480-491页

作者： Zhi-Wei Shen Shu-Feng Hu chen Zeng Wei-qing Kong Mei-fang Zhu State Key Laboratory for Modification of Chemical Fibers&Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China State Key Laboratory of Pulp and Paper Engineering School of Light Industry and EngineeringSouth China University of TechnologyGuangzhou510630China

With the global ban on plastics intensifying, the substitution of plastic with paper has garnered increasing attention. However, the inadequate water and oil repellency of pulp molding hinders its practical applications. Currently, the common method to enhance the oil and water repellency of pulp molding is by adding fluorinated water and oil repellents. Nevertheless, fluorinated compounds are environmentally and physiologically harmful. Therefore, the development of fluorine-free, water and oil repellent alternatives is crucial. In this study, chitosan and stearic acid were utilized as the first and second layers of the oil and water repellent coatings, respectively. The coated samples exhibited favorable water repellency, with a water contact angle of 116.4°, and excellent oil repellency, achieving a 12/12 rating on the kit scale. Importantly, the samples did not exhibit any leakage after being soaked in hot water and hot oil at 95±5℃ for 30 min, demonstrating remarkable performance as a barrier against hot water and oil. Moreover, the coated samples displayed outstanding mechanical properties, thermal stability, biodegradability, and recyclability. The approach presented in this study is simple, cost-effective, environmentally friendly, and represents a promising technique for producing fluoride-free, oil-and water-resistant pulp molding products.

关键词： Biomass Fluoride-free Oil-andwater-resistant Plasticfree

Geometric phase-encoded stimuli-responsive cholesteric liquid crystals for visualizing real-time remote monitoring:humidity sensing as a proof of concept

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Light(Science & Applications) 2024年第2期13卷 283-293页

作者： Shi-Long Li Zhao-Yi chen Peng chen Wei Hu Chaohong Huang Sen-Sen Li Xuejia Hu Yan-qing Lu Lu-Jian chen Department of Electronic Engineering School of Electronic Science and EngineeringXiamen University361005 XiamenChina College of Engineering and Applied Sciences Nanjing University210093 NanjingChina Fujian Key Laboratory of Ultrafast Laser Technology and Applications Xiamen University361005 XiamenChina

Liquid crystals are a vital component of modern photonics,and recent studies have demonstrated the exceptional sensing properties of stimuli-responsive cholesteric liquid ***,existing cholesteric liquid crystal-based sensors often rely on the naked eye perceptibility of structural color or the measurement of wavelength changes by spectrometric tools,which limits their practical ***,developing a platform that produces recognizable sensing signals is *** this study,we present a visual sensing platform based on geometric phase encoding of stimuli-responsive cholesteric liquid crystal polymers that generates real-time visual patterns,rather than frequency *** demonstrate this platform’s effectiveness,we used a humidity-responsive cholesteric liquid crystal polymer film encoded with a q-plate pattern,which revealed that humidity causes a shape change in the vortex beam reflected from the encoded cholesteric liquid crystal ***,we developed a prototype platform towards remote humidity monitoring benefiting from the high directionality and long-range transmission properties of laser beams carrying orbital angular *** approach provides a novel sensing platform for cholesteric liquid crystals-based sensors that offers promising practical *** ability to generate recognizable sensing signals through visual patterns offers a new level of practicality in the sensing field with stimuli-responsive cholesteric liquid *** platform might have significant implications for a broad readership and will be of interest to researchers working in the field of photonics and sensing technology.

关键词： humidity visual liquid

Experimental investigation into the salinity effect on the physicomechanical properties of carbonate saline soil

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1883-1895页

作者： Jiejie Shen qing Wang Yating chen Xuefei Zhang Yan Han Yaowu Liu College of Construction Engineering Jilin UniversityChangchun130026China Shandong Zhengyuan Geological Resources Exploration Co.Ltd. Jinan250013China China Renewable Energy Engineering Institute Beijing100120China

For engineering structures with saline soil as a filling material,such as channel slope,road subgrade,etc.,the rich soluble salt in the soil is an important potential factor affecting their safety *** study examines the Atterberg limits,shear strength,and compressibility of carbonate saline soil samples with different NaHCO3 contents in Northeast *** mechanism underlying the influence of salt content on soil macroscopic properties was investigated based on a volumetric flask test,a mercury intrusion porosimetry(MIP)test,and a scanning electron microscopic(SEM)*** results demonstrated that when NaHCO3 contents were lower than the threshold value of 1.5%,the bound water film adsorbed on the surface of clay particles thickened continuously,and correspondingly,the Atterberg limits and plasticity index increased rapidly as the increase of sodium ion ***,the bonding force between particles was weakened,the dispersion of large aggregates was enhanced,and the soil structure became ***,the compressibility increased and the shear strength(mainly cohesion)decreased by 28.64%.However,when the NaHCO3 content exceeded the threshold value of 1.5%,the salt gradually approached solubility and filled the pores between particles in the form of crystals,resulting in a decrease in soil *** cementation effect generated by salt crystals increased the bonding force between soil particles,leading to a decrease in plasticity index and an improvement in soil mechanical ***,this work provides valuable suggestions and theoretical guidance for the scientific utilization of carbonate saline soil in backfill engineering projects.

关键词： Carbonate saline soil Salt content Physicomechanical properties Bound water Microstructure

Pyruvate kinase M in germ cells is essential for sperm motility and male fertility but not spermatogenesis

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Asian Journal of Andrology 2024年第2期26卷 212-219页

作者： Gao-qing Qian Xiao-chen Wang Xi Zhang Bin Shen Qiang Liu State Key Laboratory of Reproductive Medicine and Offspring Health Nanjing Medical UniversityNanjing 211166China Shanghai Key Laboratory of Reproductive Medicine Department of HistoembryologyGenetics and Developmental BiologyShanghai Jiao Tong University School of MedicineShanghai 200025China State Key Laboratory of Molecular Biology Shanghai Key Laboratory of Molecular AndrologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghai 200031China

Male germ cells employ specific metabolic pathways throughout their developmental *** a previous study,we discovered heightened expression of pyruvate kinase M(PKM),a pivotal glycolytic enzyme,in spermatogonia and *** gain deeper insights into PKM's roles in spermatogenesis,sperm function,and male fertility,we engineered a conditional-knockout mouse model(Pkm-vkO mice)to selectively disrupt the Pkm gene within germ *** maintaining regular testicular histology and sperm morphology,the male Pkm-vko mice were infertility,characterized by significant impairments in sperm motility and adenosine triphosphate(ATP)*** addition,Pkm-null spermatozoa exhibited similar deficits in protein tyrosine phosphorylation linked to capacitation,as well as compromised performance in in vitro fertilization *** conclude,PKM's presence is not obligatory for the entirety of spermatogenesis in male germ cells;however,it emerges as a critical factor influencing sperm motility and overall male fertility.

关键词： glycolysis male fertility pyruvate kinase M sperm motility spermatogenesis

Retrieval of Antarctic sea ice freeboard and thickness from HY-2B satellite altimeter data

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Acta Oceanologica Sinica 2024年第3期43卷 87-101页

作者： Yizhuo chen Xiaoping Pang qing Ji Zhongnan Yan Zeyu Liang chenlei Zhang Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China Key Laboratory of Polar Surveying and Mapping Science Ministry of Natural ResourcesWuhan 430079China Key Laboratory of Polar Environment Monitoring and Public Governance Ministry of EducationWuhan 430079China 4 School of Geography and Tourism Anhui Normal UniversityWuhu 241002China

Antarctic sea ice is an important part of the Earth’s atmospheric system,and satellite remote sensing is an important technology for observing Antarctic sea *** Chinese Haiyang-2B(HY-2B)satellite altimeter data could be used to estimate sea ice freeboard and provide alternative Antarctic sea ice thickness information with a high precision and long time series,as other radar altimetry satellites can,needs further *** paper proposed an algorithm to discriminate leads and then retrieve sea ice freeboard and thickness from HY-2B radar altimeter *** first collected the Moderate-resolution Imaging Spectroradiometer ice surface temperature(IST)product from the National Aeronautics and Space Administration to extract leads from the Antarctic waters and verified their accuracy through Sentinel-1 Synthetic Aperture Radar ***,a surface classification decision tree was generated for HY-2B satellite altimeter measurements of the Antarctic waters to extract leads and calculate local sea surface *** then estimated the Antarctic sea ice freeboard and thickness based on local sea surface heights and the static equilibrium ***,the retrieved HY-2B Antarctic sea ice thickness was compared with the CryoSat-2 sea ice thickness and the Antarctic Sea Ice Processes and Climate(ASPeCt)ship-based observed sea ice *** results indicate that our classification decision tree constructed for HY-2B satellite altimeter measurements was reasonable,and the root mean square error of the obtained sea ice thickness compared to the ship measurements was 0.62 *** proposed sea ice thickness algorithm for the HY-2B radar satellite fills a gap in this application domain for the HY-series satellites and can be a complement to existing Antarctic sea ice thickness products;this algorithm could provide long-time-series and large-scale sea ice thickness data that contribute to research on global climate change.

关键词： HY-2B satellite altimeter classification decision tree sea ice freeboard and thickness Antarctic waters

Fully umbilical cord-derived adhesive materials enable to recruit and segregate immune cells for the reversal of acute liver failure

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Engineered Regeneration 2024年第1期5卷 70-79页

作者： Xiao Yi Feng chen Kunjie Gao Huayan Li Yuan Xie Shao Li Jiajun Zhang qing Peng Weijie Zhou Shutao Wang Jun-Bing fan Yi Gao Research Centre for Artificial Organ and Tissue Engineering&Institute of Regenerative Medicine Department of Hepatobiliary Surgery II Zhujiang Hospital Cancer Research InstituteSchool of Basic Medical SciencesSouthern Medical UniversityGuangzhouGuangdong Province 510515P R China Department of Gynecology Zhujiang HospitalSouthern Medical UniversityGuangzhou 510515P R China CAS Key Laboratory of Bio-inspired Materials and Interfacial Science CAS Center for Excellence in NanoscienceTechnical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190P R China Department of Hepato-Biliary-Pancreatic and Hernia Surgery The First People’s Hospital of ZhaoqingZhaoqingGuangdong 526000P R China Department of Pathology School of Basic Medical SciencesSouthern Medical UniversityGuangzhou 510515P R China

Inflammatory cytokine storms can trigger disease exacerbation and even death and have reached a consensus in the clinical treatment of acute organ ***,the existing strategies remain a great challenge to efficiently suppress inflammatory cytokine storms for promoting organ repair and ***,fully human umbilical cord(UC)-derived adhesive materials(UCAM)that integrate decellularized extracellular matrix(ECM)nanofiber hydrogel and homologous mesenchymal stem cells(MSCs)are demonstrated to greatly suppress inflammatory cytokine storms,demonstrating high efficacy in treating acute liver failure(ALF)in rats with 90%*** UC-derived adhesive materials have the capacity to secrete a significant quantity of cytokines by MSCs to recruit activated immune cells to migrate into their ECM nanofiber networks,segregating them away from the infection area and thereby greatly suppressing the inflammatory cytokine *** expected,the UC-derived adhesive materials can significantly promote hepatocyte proliferation to achieve functional recovery and regeneration of the liver,significantly improving the survival rate in *** fully human UC-derived adhesive materials provide a new avenue in suppressing inflammatory cytokine storms for promoting organ regeneration that would be really utility in clinical organ transplantation-related treatment.

关键词： Interfacial adhesive materials Extracellular matrix nanofibers Hydrogel Mesenchymal stem cells Acute liver failure

Effect of Fe_(2)O_(3)on the Structure,Physical Properties and Crystallization of CaO-Al_(2)O_(3)-SiO_(2)Glass

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 954-961页

作者：张峰 XIONG Dehua 谢俊张继红 HAN Jianjun chen Dequan WEN Zhongquan fan Zhenhua chen Lina SUN Tengfei State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China Hepu Research Center for Silicate Materials Industry Technology Beihai 536100China Hainan Institute of Wuhan University of Technology Sanya 430079China Shenzhen Research Institute of Wuhan University of Technology Shenzhen 518000China Chongqing Polycomp Inter-national Corporation Chongqing 400400China

The calcium aluminosilicate-based glasses(CaO-Al_(2)O_(3)-SiO_(2),CAS)with different Fe_(2)O_(3)content(0.10wt%,0.50wt%,0.90wt%,and 1.30wt%)were prepared by traditional melt-quenching *** glass network structure,thermal and mechanical properties,and crystallization behavior changes were investigated by nuclear magnetic resonance spectrometer,Fourier-transform infrared spectro-photometer,X-ray diffractometer,differential scanning calorimetry and field emission scanning electron microscope *** change of Q^(n)in glass structures reveals the glass network connectivity decreases due to the increasing content of Fe_(2)O_(3)addition,resulting in the increasing of non-bridging number in glass *** glass densities slightly rise from 2.644 to 2.681 g/cm^(3),while Vickers’s hardness increases at first,from 6.469 to 6.901 GPa,then slightly drops to 6.745 GPa,with Fe_(2)O_(3)content *** is almost no thermal expansion coefficient change from different Fe_(2)O_(3)*** glass transmittance in visible range gradually decreases with higher Fe_(2)O_(3)content,resulting from the strong absorption of Fe^(2+)and Fe^(3+)*** calculated activation energy from thermal analysis results first decreases from 282.70 to 231.18 kJ/mol,and then increases to 244.02 kJ/mol,with the Fe_(2)O_(3)content increasing from 0.10wt%to 1.30wt%.Meanwhile,the maximum Avrami constant of 2.33 means the CAS glasses exhibit two-dimensional *** of the CAS glass-ceramics samples contain main crystal phase of anorthite,the microstructure appears lamellar and columnar crystals.

关键词： calcium aluminosilicate glass network structure physical properties crystallization

Used car price prediction based on XGBoost and retention rate

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The Journal of China Universities of Posts and Telecommunications 2024年第3期31卷 72-79页

作者： Shen Yutian chen Jian Dai Min Zhang Sirui Xu Jing Wang qing College of Mechanical Engineering Yangzhou UniversityYangzhou 225127China College of Economics and Management Southeast University Chengxian CollegeNanjing 210088China Shandong Shuncheng Automobile Trade Co. LtdJinan 250000China

In order to improve the accuracy of used car price prediction,a machine learning prediction model based on the retention rate is proposed in this ***,a random forest algorithm is used to filter the variables in the *** main characteristic variables that affect used car prices,such as new car price,service time,mileage and so on,are filtered ***,the linear regression classification method is introduced to classify the test data into high and low retention rate *** that,the extreme gradient boosting(XGBoost)regression model is built for the two datasets *** prediction results show that the comprehensive evaluation index of the proposed model is 0.548,which is significantly improved compared to 0.488 of the original XGBoost ***,compared with other representative machine learning algorithms,this model shows certain advantages in terms of mean absolute percentage error(MAPE),5%accuracy rate and comprehensive evaluation *** a result,the retention rate-based machine learning model established in this paper has significant advantages in terms of the accuracy of used car price prediction.

关键词： random forest data dimensionality reduction extreme gradient boosting(XGBoost) retention rate price prediction