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Impact of Annealing on the Melt Recrystallization of a-PDLA/α-PLLA Double-layered Films

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Chinese Journal of Polymer Science 2024年第2期42卷 230-238,I0009页

作者： Yun-Peng Li Hao-ran Shen Shao-Juan Wang Hao Zhang Jian Hu rui Xin Xiao-Li Sun Shou-Ke Yan Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-plasticsQingdao University of Science&TechnologyQingdao266042China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China

Poly(lactic acid)(PLA) as a bio-based polymer with biodegradability and biocompatibility has attracted much attention. To manipulate its properties for different applications, regulation of crystal structure and crystalline morphology becomes an attractive research topic. In this work, the structure evolution of layered samples containing an amorphous poly(D-lactide)(PDLA) layer and a crystalline poly(L-lactide)(PLLA)layer with highly oriented edge-on α lamellar crystals after annealing at 150 ℃ or/and after melt-recrystallization has been studied by AFM, FTIR,and TEM combined with electron diffraction. The results demonstrate that melt recrystallization of the as-prepared sample leads to the formation of abundant randomly oriented PLA stereo-complex(PLA SC) crystals. Annealing at 150 ℃ results in the formation of a small amount of oriented PLA SC crystals at the interface. These PLA SC crystals show great impact on the recrystallization behavior of sample after melting at 190 ℃ and then crystallizing at 90 ℃. First, they impede the mutual diffusion of the overlying PDLA and underlying PLLA, and thus reduce their stereocomplexation ability as manifested by the decreased amount of PLA SC crystals. Second, they act as substrate to initiate the epitaxial crystallization of the overlying PDLA and underlying PLLA, which ensures the production of a highly oriented structure of PDLA and PLLA after melt recrystallization again.

关键词： Poly(L-lactide) Poly(D-lactide) Double layer Stereocomplex

Progress on metal-support interactions in Pd-based catalysts for automobile emission control

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Journal of Environmental Sciences 2023年第3期125卷 401-426页

作者： Yidan Cao rui ran Xiaodong Wu Zhichun Si Feiyu Kang Duan Weng Institute of Materials Research Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Tsinghua-Berkeley Shenzhen Institute Tsinghua UniversityShenzhen 518055China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

The interactions between metals and oxide supports,so-called metal-support interactions(MSI),are of great importance in heterogeneous catalysis.Pd-based automotive exhaust control catalysts,especially Pd-based three-way catalysts (TWCs),have received considerable research attention owing to its prominent oxidation activity of HCs/CO,as well as excellent thermal stability.For Pd-based TWCs,the dispersion,chemical state and thermal stability of Pd species,which are crucial to the catalytic performance,are closely associated with interactions between metal nanoparticles and their supporting matrix.Progress on the research about MSI and utilization of MSI in advanced Pd-based three-way catalysts are reviewed here.Along with the development of advanced synthesis approaches and engine control technology,the study on MSI would play a notable role in further development of catalysts for automobile exhaust control.

关键词： Palladium Three-way catalysts(TWCs) Metal-support interaction Oxide supports

Vanadium nitride quantum dots@carbon skeleton anode material synthesized via in situ oxidation initiation strategy

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Tungsten 2024年第3期6卷 561-573页

作者： Yi-Han Fu Yuan-You Peng Lei Zhao Tian-Qi He Mei-Mei Yuan Hao Dang rui Liu Fen ran State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals School of Materials Science and Engineering Lanzhou University of Technology

Vanadium nitride（VN） has received significant attention as a potential negative electrode material due to its remarkable theoretical and physical properties.However,the electrochemical performance needs to be improved due to its low specific surface area and the issue of being easily dissolved in electrolyte.Researches have shown that the composite structure of carbon-coated nano sc ale VN particles could significantly increase the specific surface area of VN,and more importantly,and the carbon matrix can effectively restrain the dissolution of VN particles in the electrolyte,thereby improving its chemical and electrochemical performance,including specific capacity and cycling stability.Herein,VN quantum dots are synthesized and protected by uniformly coating the carbon skeleton on its surface via an in situ strategy of oxidation initiation,which initiates dopamine polymerization,forming a crystalline complex of polydopamine and vanadium.After heat treatment,the product is a composite material with VN quantum dots embedded in the amorphous carbon skeleton.The resulting smallsized and crosslinked carbon particles formed a graded pore structure,more reasonable channels provided for electrolyte ions transport quickly.When the composite material was used as the negative electrode material for supercapacitors,it exhibits the specific capacity of 391.9 F·g-1at a current density of 0.5 A·g-1and excellent capacity retention rate of 83.6% after 5000cycles.The synthesis method of this quantum dot could be applied to other metal compounds and has potential applications in catalysis,environmental protection,and other fields.

关键词： In situ initiation Vanadium nitride Quantum dots Anode Supercapacitors

Evolution of HIV/AIDS Prevention and Control Policies in China:A Grounded Theory Approach

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China CDC weekly 2024年第1期6卷 12-22页

作者： Huang Li rui Gao Chichen Zhang School of Public Health Southern Medical UniversityGuangzhou CityGuangdong ProvinceChina School of Health Management Southern Medical UniversityGuangzhou CityGuangdong ProvinceChina Key Laboratory of Philosophy and Social Sciences of Colleges and Universities in Guangdong Province for Collaborative Innovation of Health Management Policy and Precision Health Service Southern Medical UniversityGuangzhou CityGuangdong ProvinceChina Graduate School Xi’an Jiaotong-Liverpool UniversitySuzhou CityJiangsu ProvinceChina School of Political Science and Public Administration Soochow UniversitySuzhou CityJiangsu ProvinceChina

Objective:This study aims to provide a theoretical foundation for the development and practical application of human immunodeficiency virus(HIV)/acquired immunodeficiency syndrome(AIDS)prevention and control policy systems in China by scrutinizing,analyzing,and synthesizing the evolution of Chinese policies in this domain.Methods:Utilizing grounded theory,we employed NVivo12 software to perform text content analysis,mining,and coding classification,along with visualization techniques,on policy texts sourced from Chinese government platforms,including the official website of China’s State Council.We considered four analytical dimensions—time,subject,type,and object.Results:The National Health Commission and the State Council emerged as the primary entities engaged in policymaking for HIV/AIDS in China.We identified four distinct stages in the evolution of these policies,culminating in a novel‘sun-shaped’HIV/AIDS prevention and control policy network model with an emphasis on‘knowledge,attitude,and practice’at its nucleus,which aligns with national conditions and societal progress.Furthermore,the focal groups of these policies have been dynamically refined and updated over time.Conclusions:Our findings introduce a‘sunshaped’HIV/AIDS prevention and control policy network model specific to China.We observed a conceptual policy shift towards prioritizing overall human health rather than confining the focus to disease treatment.Additionally,in light of China’s growing elderly population,the imperative to address HIV/AIDS prevention and control among older adults is an issue that warrants increased attention.

关键词： prevention HIV/AIDS policy

Application of silica-alumina as hydrothermally stable supports for Pt catalysts for acid-assisted soot oxidation

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Rare Metals 2023年第5期42卷 1614-1623页

作者： Shu-ran Liu Shu-Ting Luo Xiao-Dong Wu Tao-Jin Wang rui ran Duan Weng Zhi-Chun Si Shuang Liu Key Laboratory of Advanced Materials of Ministry of Education of China School of Materials Science and EngineeringTsinghua UniversityBeijing100084China International Graduate School at Shenzhen Tsinghua UniversityShenzhen518055China School of Materials Science and Engineering Ocean University of ChinaQingdao266100China

In this work,silica-alumina mixed oxides with different SiO_(2)contents(5%and 30%)were adopted as acidic supports for platinum catalysts for soot oxidation.The obtained catalysts were hydrothermally aged in 10%H_(2)0/air at 750℃for 20 h.The catalysts were characterized by X-ray diffraction(XRD),N_(2)adsorption,inductively coupled plasma(ICP),CO chemisorption,NH3temperature-programmed desorption(TPD),infrared(IR)spectroscopy of CO adsorption,temperature-programmed oxidation(TPO)of NO,and TPD of NO_(x).The surface acidity of catalyst was positive correlated with the content of SiO_(2),which kept platinum in metallic and partially oxidized states in an oxidizing atmosphere.Compared with sulfation treatment on the alumina support,the application of SiO_(2)-Al_(2)O_(3)mixed oxides does not result in the coverage of Pt active sites and the prepared catalysts exhibit excellent activity for NO oxidation.They promote NOxpreferential adsorption on soot and decomposition of surface oxygenated compounds(SOCs)as the sulfated Pt/Al_(2)O_(3)catalyst does.

关键词： Platinum Acidic support Diesel soot Hydrothermal aging

Delayed neurological dysfunction following posterior laminectomy with lateral mass screw fixation:A case report and review of literature

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World Journal of Clinical Cases 2024年第7期12卷 1356-1364页

作者： rui-Zhong Yan Chao Chen Chu-ran Lin Yan-Hui Wei Zhi-Jian Guo Ya-Kun Li Quan Zhang He-Yi Shen Hao-Lin Sun Department of Orthopedics Taiyuan Central HospitalTaiyuan 030009Shanxi ProvinceChina Department of Orthopedics Graduate School Shanxi University of Traditional Chinese MedicineTaiyuan 030024Shanxi ProvinceChina Department of Orthopedics Peking University First HospitalBeijing 100034China

BACKGROUND While most complications of cervical surgery are reversible,some,such as symptomatic postoperative spinal epidural hematoma(SEH),which generally occurs within 24 h,are associated with increased morbidity and mortality.Delayed neurological dysfunction is diagnosed in cases when symptoms present>3 d postoperatively.Owing to its rarity,the risk factors for delayed neurological dysfunction are unclear.Consequently,this condition can result in irreversible neurological deficits and serious consequences.In this paper,we present a case of postoperative SEH that developed three days after hematoma evacuation.CASE SUMMARY A 68-year-old man with an American Spinal Injury Association(ASIA)grade C injury was admitted to our hospital with neck pain and tetraplegia following a fall.The C3-C7 posterior laminectomy and the lateral mass screw fixation surgery were performed on the tenth day.Postoperatively,the patient showed no changes in muscle strength or ASIA grade.The patient experienced neck pain and subcutaneous swelling on the third day postoperatively,his muscle strength decreased,and his ASIA score was grade A.Magnetic resonance imaging showed hypointense signals on T1 weighted image(T1WI)and T2WI located behind the epidural space,with spinal cord compression.Emergency surgical intervention for the hematoma was performed 12 h after onset.Although hypoproteinemia and pleural effusion did not improve in the perioperative period,the patient recovered to ASIA grade C on day 30 after surgery,and was transferred to a functional rehabilitation exercise unit.CONCLUSION This case shows that amelioration of low blood albumin and pleural effusion is an important aspect of the perioperative management of cervical surgery.Surgery to relieve the pressure on the spinal cord should be performed as soon as possible to decrease neurological disabilities.

关键词： Delayed postoperative spinal epidural hematoma Complications Spinal surgery Hypoproteinemia Risk factor Case report

Origin and tectonic setting of low-Si alkaline magma

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Science China Earth Sciences 2024年第5期67卷 1417-1435页

作者： Qiushi ZHOU rui WANG State Key Laboratory of Geological Processes and Mineral Resources and Institute of Earth SciencesChina University of GeosciencesBeijing 100083China Frontiers Science Center for Deep-time Digital Earth China University of Geosciences(Beijing)Beijing 100083China

Despite of the relatively rare occurrence of alkaline igneous rocks on Earth, they are the most diverse group of igneous rocks due to variations in their mineral assemblages and geochemical compositions. Alkaline igneous rocks are generally characterized by Si undersaturation, and K-Na(and in some cases C) enrichment. Although there is no unified alkaline igneous rock classification scheme, diagrams such as total alkalis-SiO_(2) or K_(2)O-SiO_(2) can be used to classify alkaline igneous rocks. The origins of silica-saturated alkaline rocks(SiO_(2)>52 wt.%) are relatively complex because multiple episodes of magmatism are often involved, therefore most studies have focused on the origins of silica-undersaturated alkaline magmas.Numerous experimental petrological studies have been conducted in the past few decades. Initially, it was considered that enrichment of trace elements was only achieved by low-degree partial melting of mantle peridotite, but the experimental melts could not reproduce the geochemical composition of natural alkaline igneous rocks. Subsequent studies have focused on carbonate-bearing eclogites that represent the average component of subducted oceanic crust. Although experimental studies indicate that silica-undersaturated and alkali-oversaturated melts can be generated from eclogites, some studies have considered that natural silica-undersaturated alkaline igneous rocks are the result of multi-stage source enrichment by incompatible elements. Low-degree partial melts of the mantle can be emplaced in the lithospheric mantle, forming veins consisting of phlogopite, amphibole, and pyroxene. Melting experiments including these components show that the produced melts better reproduce the naturally occurring silica-undersaturated alkaline magmas. Silica-deficient alkaline igneous rocks occur in various tectonic settings. Those in intraplate and divergent settings(i.e., mainly continental rifts) normally involve contributions from recycled components such as subducted slabs at the mantle transition z

关键词： Alkaline igneous rock Tectonic setting Petrogenesis Big data

Deciphering and integrating invariants for neural operator learning with various physical mechanisms

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National Science Review 2024年第4期11卷 111-122页

作者： rui Zhang Qi Meng Zhi-Ming Ma Academy of Mathematics and Systems Science Chinese Academy of Sciences(CAS) Microsoft Research

Neural operators have been explored as surrogate models for simulating physical systems to overcome the limitations of traditional partial differential equation(PDE) solvers. However, most existing operator learning methods assume that the data originate from a single physical mechanism, limiting their applicability and performance in more realistic scenarios. To this end, we propose the physical invariant attention neural operator(PIANO) to decipher and integrate the physical invariants for operator learning from the PDE series with various physical mechanisms. PIANO employs self-supervised learning to extract physical knowledge and attention mechanisms to integrate them into dynamic convolutional layers.Compared to existing techniques, PIANO can reduce the relative error by 13.6%–82.2% on PDE forecasting tasks across varying coefficients, forces or boundary conditions. Additionally, varied downstream tasks reveal that the PI embeddings deciphered by PIANO align well with the underlying invariants in the PDE systems, verifying the physical significance of PIANO.

关键词： neural operator PDE solver contrastive learning physical invariants

The Role of Adipose Tissue-derived Exosomes in Chronic Metabolic Disorders

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Current Medical Science 2024年第3期44卷 463-474页

作者： rui HE Yong CHEN Division of Endocrinology Department of Internal MedicineTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Laboratory of Endocrinology & Metabolism Key Laboratory of Vascular Aging of the Ministry of EducationTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Branch of National Clinical Research Center for Metabolic Diseases Wuhan430030China

Excessive fat deposition in obese subjects promotes the occurrence of metabolic diseases,such as type 2 diabetes mellitus(T2DM),cardiovascular diseases,and non-alcoholic fatty liver disease(NAFLD).Adipose tissue is not only the main form of energy storage but also an endocrine organ that not only secretes adipocytokines but also releases many extracellular vesicles(EVs)that play a role in the regulation of whole-body metabolism.Exosomes are a subtype of EVs,and accumulating evidence indicates that adipose tissue exosomes(AT Exos)mediate crosstalk between adipose tissue and multiple organs by being transferred to targeted cells or tissues through paracrine or endocrine mechanisms.However,the roles of AT Exos in crosstalk with metabolic organs remain to be fully elucidated.In this review,we summarize the latest research progress on the role of AT Exos in the regulation of metabolic disorders.Moreover,we discuss the potential role of AT Exos as biomarkers in metabolic diseases and their clinical application.

关键词： exosome adipose tissue obesity diabetes chronic metabolic disorder miRNA