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The effect of Ti and Zr content on the structure,mechanics and energy-release characteristics of Ti—Zr—Ta alloys

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Defence Technology（防务技术） 2024年第1期31卷 343-350页

作者： jia-yu Meng Jing-zhi He Bin Zhang Jin Chen Shun li Dun Niu yu Tang Xi’an Modern Chemistry Research Institute Xi'an710065China College of Aerospace Science and Engineering National University of Defense TechnologyChangsha410073China

Energetic structural materials(ESMs)are a new type of structural materials with bearing and damage *** this work the microstructure,mechanical properties and energy release characteristics of multi-element Ti-Zr-Ta alloys with good casting performance were *** microstructure of the Ti_(x)ZrTa alloys gradually change from BCC+HCP to single BCC structure with the increase of *** the Ti_(2)Zr_(y)Ta alloys was still uniform and single BCC structure with the increase of *** evolution of microstructure and composition then greatly affect the mechanical properties and energy-release characteristics of Ti-Zr-Ta *** synergistic effect of dual phase structure increases the fracture strain of Ti_(x)ZrTa(x=0.2,0.5)with the Ti content decreases,while the fracture strain of Ti_(x)ZrTa(x=2.0,3.0,4.0)gradually increase with the Ti content increases caused by the annihilation of the obstacles for dislocation *** as Zr content increases,the fracture strain of Ti_(2)Zr_(y)Ta alloys decrease,then the oxidation reaction rate and fragmentation degree gradually *** higher oxidation rate and the lager exposed oxidation area jointly leads the higher releasing energy efficiency of Ti_(x)ZrTa alloys with low Ti content and Ti_(2)Zr_(y)Ta alloys with high Zr content.

关键词： Energetic structural materials Ti-Zr-Ta Multi-element alloy Energy release characteristics

Synthetic auxotrophs accelerate cell factory development through growth-coupled models

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 73-87页

作者： liangpo li linwei yu Xinxiao Sun Qipeng yuan Xiaolin Shen jia Wang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

The engineering of microbial cell factories for the production of high-value chemicals from renewable resources presents several challenges,including the optimization of key enzymes,pathway fluxes and metabolic *** these challenges involves the development of synthetic auxotrophs,a strategy that links cell growth with enzyme properties or biosynthetic *** linkage allows for the improvement of enzyme properties by in vivo directed enzyme evolution,the enhancement of metabolic pathway fluxes under growth pressure,and remodeling of metabolic networks through directed strain *** advantage of employing synthetic auxotrophs lies in the power of growth-coupled selection,which is not only high-throughput but also labor-saving,greatly simplifying the development of both strains and *** auxotrophs play a pivotal role in advancing microbial cell factories,offering benefits from enzyme optimization to the manipulation of metabolic networks within single ***,this strategy extends to coculture systems,enabling collaboration within microbial *** review highlights the recently developed applications of synthetic auxotrophs as microbial cell factories,and discusses future perspectives,aiming to provide a practical guide for growth-coupled models to produce value-added chemicals as part of a sustainable biorefinery.

关键词： synthetic auxotrophs growth-coupled directed enzyme evolution pathway flux directed strain evolution coculture

Effect of Sc on Al_(3)Fe phase and mechanical properties of as-cast AA5052 aluminum alloy

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China Foundry 2024年第3期21卷 257-264页

作者： Yang li Qing yu Feng-feng Chen jia-wen He Hong-mei Yang Meng-nie li Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

The AA5052 aluminum alloy is widely used in automobile and aerospace manufacturing,and with the development of light-weight alloys,it is required that these materials exhibit better mechanical *** studies have demonstrated that the addition of Sc to aluminum alloys can improve both the microstructure and properties of the *** this study,the effect of Sc on the Fe-rich phase and properties of the AA5052 aluminum alloy was studied by adding 0%,0.05%,0.2%,and 0.3%*** results show that with the increase of Sc,the coarse needle-like Fe-rich phase gradually transforms into Chinese-script and then nearly spherical particles,reduce the size of Fe-rich phase,and refine the grain with increase of high angle grain boundaries(HAGBs).These microstructure changes enhance the strength of the AA5052 alloy through Sc *** ductility of the alloy is obviously improved because the addition of a lower amount of Sc changes the morphology of Fe-rich phase from needle-like into a Chinese-script,and it is subsequently reduced as a result of significant increase in HAGBs with increasing Sc content.

关键词： AA5052 aluminum alloy Al3Fe phase mechanical properties grain boundary

Breast metastases from rectal carcinoma

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Chinese Medical Journal 2011年第8期124卷 1267-1269页

作者： li jia FANG yu li Ang li Fei Department of General Surgery Xuanwu Hospital Capital MedicalUniversity Beijing 100053 China

Metastases to the breast from extramammary neoplasms are very rare, constituting 2.7% of all malignant breast tumours. The most common primary tumor metastatic to the breast is primary breast cancer. Rectal cancer metastasizing to the breast is extremely rare. We report a case of aggressive rectal carcinoma with metastasis to the breast.

关键词： breast metastases rectal carcinoma malignant

Epidemiology of congenital diaphragmatic hernia among 24 million Chinese births:a hospital-based surveillance study

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World Journal of Pediatrics 2024年第7期20卷 712-722页

作者： Zhi-yu Chen Jing Tao Wen-li Xu yu-Yang Gao Wen-Yan li Zhen liu jia-yuan Zhou li Dai National Center for Birth Defects Monitoring West China Second University HospitalSichuan UniversityNo.17 Section 3 RenminnanluChengdu 610041China The Joint Laboratory for Pulmonary Development and Related Diseases West China Institute of Women and Children’s HealthWest China Second University HospitalSichuan UniversityChengduChina Key Laboratory of Birth Defects and Related Diseases of Women and Children Ministry of EducationSichuan UniversityChengduChina NHC Key Laboratory of Chronobology Sichuan UniversityChengduChina Med‑X Center for Informatics Sichuan UniversityChengduChina

Background The prevalence of congenital diaphragmatic hernia(CDH)varies across countries,with limited information available on its epidemiology in *** study aimed to investigate the prevalence,time trends,and perinatal outcomes of CDH in China,as well as its associated malformations and potential associations with maternal and infant *** This study included all birth and CDH cases from the Chinese Birth Defects Monitoring Network between 2007 and 2019,with CDH cases classified as either isolated or *** employed the joinpoint regression model to calculate the trends of prevalence and the annual percent change,with Poisson regression used for adjusted prevalence rate ratios.A P value≤0.05 was considered statistically *** A total of 4397 CDH cases were identified among 24,158,029 births in the study period,yielding prevalence rates of 1.82,1.13 and 0.69 per 10,000 for overall,isolated,and associated CDH,*** prevalence of each type of CDH increased over *** prevalence of overall CDH varied significantly by infant sex(male ***,1.91/10,000 vs.1.63/10,000),maternal residence(urban ***,2.13/10,000 vs.1.45/10,000),maternal age(lies were the most common malformations associated with *** with associated CDH had a higher risk of premature birth and perinatal death than those with isolated *** The increasing prevalence and high perinatal mortality rate of CDH highlight the need for further etiological,epidemiological,and clinical studies among the Chinese population.

关键词： China Congenital diaphragmatic hernia Epidemiology Prevalence

Novel heterozygous USH1C mutation impacts hair cell mechanotransduction and causes progressive hearing loss

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Science Bulletin 2024年第2期69卷 167-172页

作者： Yanyan jia Gaogan jia Luo Guo Nan Song yu-Meng Wang Luoying jiang Yilai Shu Yan Chen Shujia Zhu Huawei li Wenyan li ENT Institute and Otorhinolaryngology Department of Eye&ENT Hospital State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain ScienceFudan UniversityShanghai 200031China Institutes of Biomedical Sciences Fudan UniversityShanghai 200032China NHC Key Laboratory of Hearing Medicine(Fudan University) Shanghai 200031China The Institutes of Brain Science and the Collaborative Innovation Center for Brain Science Fudan UniversityShanghai 200032China Shanghai Center for Brain Science and Brain-Inspired Intelligence Technology Shanghai 201210China Institute of Neuroscience State Key Laboratory of NeuroscienceCAS Center for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai 200031China Department of Cardiology and Institute for Developmental and Regenerative Cardiovascular MedicineXinhua Hospital Affiliated to Shanghai Jiaotong University School of MedicineShanghai 200092China

Hearing loss is one of the most common sensory disorders worldwide,affecting approximately 466 million people,including 34 million children[1].Genetic mutations accounts for approximately 60%of inherited hearing loss cases[2,3].These genetic changes result in a wide variety of clinical manifestations,ranging from nonsyndromic hearing loss(NSHL)to over 400 syndromes involving hearing loss and from mild adult-onset hearing loss to profound congenital deafness,covering the entire spectrum of Mendelian inheritance.

关键词： mec hearing approximate

Surface vitrification of carbon by laser treatment: Insights of glass formation from molecular dynamics

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Journal of Advanced Ceramics 2024年第6期13卷 729-735页

作者： Yanhui Zhang Haifeng yu Yongying jia Zhisheng Zhao li-Min Wang Riping liu Center for Advanced Structural Materials State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdao 066004China

Microstructural modification of carbon materials,such as carbon fibers(Cf)and pyrolytically deposited carbon,is important for engineering ***,the regulation of these materials is not an effortless *** understand the impacts of thermal spikes from pulsed laser processing on the structural adaptation of amorphous carbon(a-C),we performed melt quenching by molecular dynamics(MD)*** results confirm that the vitrification behavior of carbon can be tuned by adjusting the cooling rate(R),which is controlled by the thermal spikes of laser ***,we set up a two-step way to locate the critical cooling rate(R_(c))of monoatomic carbon,which is refined by the sharp change in the environmental similarity *** this novel technique,we demonstrate that the ordering degree and the local atomic motif can be largely modified by going across a bar of 100 K/ps,which is extracted as the critical cooling rate to ensure the complete amorphization of *** approach provides a criterion for both experimentally processing and theoretically simulating a-C ***,this work provides guidelines on how to tune the amorphous carbon structures of engineering materials and provides an outlook for the wonderland of amorphous carbon materials.

关键词： molecular dynamics(MD) structural order carbon fibers(Cf) vitrification critical cooling rate(R_(c))

Applicability and improvement of different potential evapotranspiration models in different climate zones of China

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Ecological Processes 2024年第1期13卷 262-282页

作者： Zedong li Yiran li Xinxiao yu Guodong jia Peng Chen Pengfei Zheng yusong Wang Bingbing Ding Key Laboratory of Soil & Water Conservation and Desertification Combating of Ministry of Education Beijing Forestry University College of Horticulture and Forestry Sciences Tarim University State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical Science Beijing Normal University

Background Accurate estimation of potential evapotranspiration(PET) is the key for studying land-air interaction hydrological processes. Several models are used to estimate the PET based on standardized meteorological data. Although combination-based models have the highest level performance estimation of PET, they require more meteorological data and may therefore be difficult to apply in areas lacking meteorological observation *** The results showed significant differences in the spatial trends of PET calculated by different models in China, the Doorenbots–Pruitts model revealed the highest PET(1902.6 mm), and the Kuzmin model revealed the lowest PET(349.6 mm), with the largest difference being 5.5 times. The Romanenko and the Rohwer models were the recommended temperature-based and aerodynamic-based models. On the other hand, the Abtew model was more suitable for arid and semi-arid regions, while the Priestley–Taylor model was more suitable for humid regions. Combination-based models revealed ideal calculation accuracies, among which the Penman–Monteith model was the best option for PET *** The accuracy range of Romanenko, Rohwer, Abten, Priestley Taylor, and Penman Monteith models improved in MPZ and TCZ is higher than that improved in TMZ and SMZ. This does not mean that the improved models have higher accuracy in MPZ and TCZ than in TMZ and SMZ. On the contrary, the original model performed poorly in MPZ and TCZ, so the improved accuracy was relatively large. The unimproved model was already more suitable in TMZ and SMZ, so the improved accuracy was relatively small. Therefore, regional calibration of the PET models can improve the accuracy and applicability of PET calculation, providing a reference for studying hydrological processes in different climatic zones.

关键词： Potential evapotranspiration Climatic zone Temperature-based model Aerodynamic-based model Radiation-based model Combination-based model Model calibration

Megafossils of Betulaceae from the Oligocene of Qaidam Basin and their paleoenvironmental and phytogeographic implications

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Plant Diversity 2024年第1期46卷 101-115页

作者： Tao Yang jia-Hao Cai Yan-Zhi Dai Hong-yu Chen Lei Han li Zhang Wei-yu liang Xu-Jun li Wen-jia li Jing-yu Wu San-Ping Xie De-Fei Yan School of Earth Sciences and Key Laboratory of Mineral Resources in Western China(Gansu Province) Lanzhou UniversityLanzhou 730000China Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China Center for Research and Education on Biological Evolution and Environments School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023China

Understanding the paleoenvironment and phytogeographical history of the Tibetan Plateau,China relies on discovering new plant *** Qaidam Basin has long been regarded as an ideal‘field laboratory’to investigate the paleoclimate and paleobiological evolution of the northern Tibetan ***,fossil angiosperms from the Qaidam Basin are rare,and our knowledge of its paleovegetation is ***,we report fossil leaves and fruits of Betulaceae found from the Oligocene Shangganchaigou Formation of northwestern Qaidam Basin(Huatugou area).Comparative morphological analysis led us to assign the fruits to the Betula subgenus Betula and the leaves to Carpinus *** findings,together with other reported fossil plants from the same locality,reveal a close floristic linkage between the Qaidam Basin and Europe during the *** northern pathway of this floristic exchange may have crossed through the Qaidam Basin during the late *** floristic linkage may have been facilitated by the continuous narrowing of the Turgai Strait and stronger westerlies,which transported moisture and provided favorable climatic ***,fossil plants collected from the Qaidam Basin suggest that during the Oligocene this region had warm and humid deciduous broad-leaf forest,which differs from the region’s modern vegetation and indicates that the Qaidam Basin may have been a suitable region for these plants to flourish and spread during the Oligocene.

关键词： Paleoenvironment Biogeography Betulaceous fossil Qaidam basin Tibetan Plateau Oligocene