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Pressure induced insulator to metal transition in quantum spin liquid candidate NaYbS_(2)
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作者 贾雅婷 龚春生 +6 位作者 李芷文 刘以轩 赵建发 王哲 雷和畅 于润泽 靳常青 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期369-372,共4页
Pressure induced insulator to metal transition followed by the appearance of superconductivity has been observed recently in inorganic quantum spin liquid candidate NaYbSe_(2).In this paper,we study the properties of ... Pressure induced insulator to metal transition followed by the appearance of superconductivity has been observed recently in inorganic quantum spin liquid candidate NaYbSe_(2).In this paper,we study the properties of isostructural compound NaYbS_(2)under pressure.It is found that the resistance of Na YbS_(2)single crystal exhibits an insulating state below 82.9 GPa,but with a drop of more than six orders of magnitude at room temperature.Then a minimum of resistance is observed at about 100.1 GPa and it moves to lower temperature with further compression.Finally,a metallic state in the whole temperature range is observed at about 130.3 GPa accompanied by a non-Fermi liquid behavior below 100 K.The insulator to metal transition,non-monotonic resistance feature and non-Fermi liquid behavior of NaYbS_(2)under pressure are similar to those of NaYbSe_(2),suggesting that these phenomena might be the universal properties in NaLnCh_(2)(Ln=rare earth,Ch=O,S,Se)system. 展开更多
关键词 high pressure quantum spin liquid insulator to metal transition NaYbS_(2)
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Pleniglacial millennium-scale climate variations in northern China based on records from the Salawusu River Valley 被引量:7
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作者 FengNian WANG BaoSheng li +6 位作者 JiangLong WANG XiaoHao WEN DongFeng NIU zhiwen li YueJun SI YiHua GUO ShuHuan DU 《Journal of Arid Land》 SCIE 2012年第3期231-240,共10页
Situated in the Salawusu River Valley, southeast of China's Mu Us Desert, the MGS2 (Milanggouwan section) portion of the Milanggouwan stratigraphic section records 5.5 sedimentary cycles consisting of alternations ... Situated in the Salawusu River Valley, southeast of China's Mu Us Desert, the MGS2 (Milanggouwan section) portion of the Milanggouwan stratigraphic section records 5.5 sedimentary cycles consisting of alternations between dune sand deposits and fluvial or lacustrine facies. We analyzed the grain-size and CaCO3 distributions in MGS2, and found that Mz (mean particle diameter) and o (standard deviation) displayed clear variations in peaks and valleys within different sedimentary facies. The CaCO3 content averaged 0.4% in the dune sand deposits, 1.43% in the fluvial facies, and 8.82% in the lacustrine facies. Both the grain-size distribution and CaCO3 contents, which equal the indicators for the alternation among the sedimentary facies, suggest the occurrence of 5.5 cycles. These results suggest that the observed cycles mainly resulted from fluctuations between a cold and dry winter monsoon climate and a warm and humid summer monsoon climate, and that the MGS2 portion experienced at least 5.5 fluctuations between these two extremes. This high-frequency climatic fluctuation indicates a strong influence of millennium-scale variations in the strength of the East Asian winter and summer monsoons in our study area during the Pleniglacial. 展开更多
关键词 Salawusu River Valley Pleniglacial paleoclimatic indices CACO3 GRAIN-SIZE
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Nanocellulose Composites—Properties and Applications 被引量:23
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作者 Chang Ma MingGuo Ma +1 位作者 zhiwen li Bin Wang 《Paper And Biomaterials》 2018年第2期51-63,共13页
Nanocellulose composites combine the advantages of nanocellulose and composites. Recently, nanocellulose composites have been received more attentions due to their improved properties and promising broad applications.... Nanocellulose composites combine the advantages of nanocellulose and composites. Recently, nanocellulose composites have been received more attentions due to their improved properties and promising broad applications. In the past, rapid progress has been made in the synthesis, properties, and mechanism of nanocellulose composites and potential applications were reported. There are a few reports on the increasing applications of nanocellulose composites with focus on the biomedical field, environmental field, electrode and sensor applications. In this article, the recent development of nanocellulose composites was reviewed via some typical examples. In addition to the synthesis methods, improved properties and potential applications were discussed. The problems and future applications of nanocellulose composites were also suggested. 展开更多
关键词 纳米纤维素 复合材料 材料学 发展现状
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Superconductivity above 30 K Achieved in Dense Scandium
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作者 何鑫 张昌玲 +15 位作者 李芷文 张思佳 冯少敏 赵建发 卢可 闵保森 彭毅 望贤成 宋静 王鲁红 Saori I.Kawaguchi 吉诚 李冰 刘浩哲 J.S.Tse 靳常青 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第10期108-111,共4页
Superconductivity is one of most intriguing quantum phenomena,and the quest for elemental superconductors with high critical temperature(T_(c))is of great scientific significance due to their relatively simple materia... Superconductivity is one of most intriguing quantum phenomena,and the quest for elemental superconductors with high critical temperature(T_(c))is of great scientific significance due to their relatively simple material composition and the underlying mechanism.Here we report the experimental discovery of densely compressed scandium(Sc)becoming the first elemental superconductor with T_(c)breaking into 30 K range,which is comparable to the T_(c)values of the classic La-Ba-Cu-O or LaFeAsO superconductors.Our results show that T_(c)^(onset)of Sc increases from~3K at around 43GPa to~32K at about 283GPa(T_(c)^(zero)~31 K),which is well above liquid neon temperature.Interestingly,measured T_(c)shows no sign of saturation up to the maximum pressure achieved in our experiments,indicating that T_(c)may be even higher upon further compression. 展开更多
关键词 TEMPERATURE mechanism SUPERCONDUCTOR
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Fabrication of MXene-Bi_(2)WO_(6)heterojunction by Bi_(2)Ti_(2)O_(7)hinge for extraordinary LED-light-driven photocatalytic performance
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作者 zhiwen li liangliang Xu +6 位作者 Zaheer Ud Din Babar Ali Raza Yifei Zhang Xinrui Gu Yu-Xin Miao Zhen Zhao Gao li 《Nano Research》 SCIE EI CSCD 2024年第6期4729-4736,共8页
Heterojunction composites with intimate interfaces can shorten the diffusion distance,which leads to a shorter path for photogenerated carriers,thereby increasing photocatalytic activity.Herein,we report the fabricati... Heterojunction composites with intimate interfaces can shorten the diffusion distance,which leads to a shorter path for photogenerated carriers,thereby increasing photocatalytic activity.Herein,we report the fabrication of Ti_(3)C_(2)-Bi_(2)WO_(6)(TC-BW)heterojunctions hinged by Bi_(2)Ti_(2)O_(7)joints via an in situ hydrothermal reaction of Ti_(3)C_(2)in the presence of Na_(2)WO_(4)and Bi(NO_(3))_(3).The TC-BW was characterized using X-ray diffraction(XRD),scanning transmission electron microscopy(STEM),and Raman spectroscopy.TC-BW showed superior photocatalytic activity(productivity over 15TC-WB reaches up to 5.0 mmolreacted BA·gcat.^(−1)·h^(−1))in the oxidation of benzyl alcohol using light-emitting diode(LED)light,arising from the surface defects and intimate heterojunction interface between the Ti_(3)C_(2)MXene and Bi_(2)WO_(6)nanosheets.TC-BW heterojunctions provide an enhanced separation efficiency of photogenerated charges,which in turn yields superior photocatalytic activity.Furthermore,it is well substantiated by density functional theory(DFT)calculations.In summary,this study elucidates the preparation of heterojunction composites with intimate interfaces for highly efficient photooxidation. 展开更多
关键词 MXene-Bi_(2)WO_(6) HETEROJUNCTION LED-light-driven photocatalysis Bi_(2)Ti_(2)O_(7) photooxidation
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Erratum to:Fabrication of MXene-Bi_(2)WO_(6)heterojunction by Bi_(2)Ti_(2)O_(7)hinge for extraordinary LED-light-driven photocatalytic performance
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作者 zhiwen li liangliang Xu +6 位作者 Zaheer UdDin Babar Ali Raza Yifei Zhang Xinrui Gu Yu-Xin Miao Zhen Zhao Gao li 《Nano Research》 SCIE EI CSCD 2024年第6期5760-5760,共1页
In the first page of the original version of this paper,the Received date should be“9 October 2023”instead of“9 October 2013”.
关键词 performance (2)
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Is there an optimal time to initiate adjuvant chemotherapy to predict benefit of survival in non-small cell lung cancer? 被引量:2
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作者 Yutao liu Xiaoyu Zhai +3 位作者 Junling li zhiwen li Di Ma Ziping Wang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2017年第3期263-271,共9页
Objective: Adjuvant chemotherapy (AC) after curative resection is known to improve the survival of patients with non-small cell lung cancer (NSCLC); however, few studies have reported the correlation between the time ... Objective: Adjuvant chemotherapy (AC) after curative resection is known to improve the survival of patients with non-small cell lung cancer (NSCLC); however, few studies have reported the correlation between the time to initiation of AC (TTAC) and survival in NSCLC patients. Methods: The clinical data of 925 NSCLC patients who received curative resection and post-operative AC at the Cancer Hospital of Chinese Academy of Medical Sciences between 2003 and 2013 were retrospectively analyzed. TTAC was measured from the date of surgery to the initiation of AC. Disease-free survival (DFS) was defined as the duration from surgery to the time of tumor recurrence or last follow-up evaluation. The optimal cut-off value of TTAC was determined by maximally selected log-rank statistics. The DFS curve was estimated using the Kaplan-Meier method, and the Cox proportional hazards regression model was used to identify risk factors independently associated with DFS. Propensity score matching (PSM) was performed for survival analysis using the match data. Results: The optimal discriminating cut-off value of TTAC was set at d 35 after curative resection based on which the patients were assigned into two groups: group A (<= 35 d) and group B (> 35 d). There was no significant difference in the DFS between the two groups (P=0.246), indicating that the TTAC is not an independent prognostic factor for DFS. A further comparison continued to show no significant difference in the DFS among 258 PSM pairs (P=0.283). Conclusions: There was no significant correlation between the TTAC and DFS in NSCLC patients. Studies with larger samples are needed to further verify this conclusion. 展开更多
关键词 Non-small cell lung cancer (NSCLC) adjuvant chemotherapy time to adjuvant chemotherapy(TTAC) disease-free survival
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Regional gray matter atrophy and neuropsychologcal problems in relapsing-remitting multiple sclerosis
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作者 Aiyu lin Fuyong Chen +5 位作者 Fang liu zhiwen li Ying liu Shifang lin Xiaoyi Wang Jiting Zhu 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第21期1958-1965,共8页
In multiple sclerosis, gray matter atrophy is extensive, and cognitive deficits and mood disorders are frequently encountered. It has been conjectured that focal atrophy is associated with emotional decline. However, ... In multiple sclerosis, gray matter atrophy is extensive, and cognitive deficits and mood disorders are frequently encountered. It has been conjectured that focal atrophy is associated with emotional decline. However, conventional MRI has revealed that the pathological characteristics cannot fully account for the mood disorders. Moreover, there is no correlation between cognitive disorders and MRI results in clinically isolated syndromes or in cases of definite multiple sclerosis. In this casecontrol study, voxel-based morphometric analysis was performed on 11 subjects with relapsing-remitting multiple sclerosis, and the results show that these patients exhibit gray matter atrophy. Moreover, the gray matter atrophy in the superior and middle gyri of the right frontal lobe in patients with multiple sclerosis was correlated with scores from the Hamilton Anxiety Rating Scale. The scores obtained with the Repeatable Battery for the Assessment of Neuropsychological Status were associated with gray matter atrophy in the middle gyrus of the left frontal lobe, the superior and middle gyrus of the right frontal lobe, the middle gyrus of the left cingulate, the superior and middle gyri of the left frontal lobe, and the triangular area of the left frontal lobe. However, there was no statistical significance. These findings suggest that the cingulate and frontal cortices of the dominant hemisphere are the most severely atrophic regions of the brain, and this atrophy is correlated with cognitive decline and emotional abnormalities. 展开更多
关键词 neural regeneration NEURODEGENERATION MRI relapsing-remitting multiple sclerosis gray matter atrophy COGNITIVE MOOD voxel-based morphometry NEUROREGENERATION
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Current study and prospect of the Old Red Sand along the southeast coast of China
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作者 zhiwen li YuXiang Dong +1 位作者 BaoSheng li FengNian Wang 《Research in Cold and Arid Regions》 2012年第6期462-471,共10页
The Old Red Sand is composed of brown-red, red, or orange-yellow semi-cemented and medium-fine sand sediment, mainly dis- tributed along the southeast coast of China. Based on previous studies, this paper summarizes t... The Old Red Sand is composed of brown-red, red, or orange-yellow semi-cemented and medium-fine sand sediment, mainly dis- tributed along the southeast coast of China. Based on previous studies, this paper summarizes the distribution and forms, sedi- mentary characteristics, formation mechanism, developing age, reddening process and the paleo-environment, suggesting that the Old Red Sand is mainly aeolian sediment of Late Pleistocene Age. The reddening process is mainly the result of decomposition and oxidation of iron-containing minerals caused by hot and humid tropical and sub-tropical climate. In this study, existing prob- lems are discussed and the prospect of further research is presented as well. 展开更多
关键词 southeast coast of China Old Red Sand current study situation PROSPECTS
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Morphology effects in MnCeO_(x)solid solution-catalyzed NO reduction with CO:Active sites,water tolerance,reaction pathway
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作者 Quanquan Shi Yifei Zhang +4 位作者 zhiwen li Zhongkang Han liangliang Xu Alfons Baiker Gao li 《Nano Research》 SCIE EI CSCD 2023年第5期6951-6959,共9页
Morphological effects of nanoparticles are crucial in many solid-catalyzed chemical transformations.We herein prepared two manganese-ceria solid solutions,well-defined MnCeO_(x)nanorods and MnCeO_(x)-nanocubes,exposin... Morphological effects of nanoparticles are crucial in many solid-catalyzed chemical transformations.We herein prepared two manganese-ceria solid solutions,well-defined MnCeO_(x)nanorods and MnCeO_(x)-nanocubes,exposing preferentially(111)and(100)facets of ceria,respectively.The incorporation of Mn dopant into ceria lattice strongly enhanced the catalytic performance in the NO reduction with CO.MnCeO_(x)(111)catalyst outperformed MnCeO_(x)(100)counterpart due to its higher population density of oxygen vacancy defects.In-situ infrared spectroscopy investigations indicated that the reaction pathway over MnCeO_(x)and pristine CeO_(2)is similar and that besides the direct pathway,an indirect pathway via adsorbed hyponitrite as an intermediate cannot be ruled out.X-ray photoelectron and Raman spectroscopies as well as first-principles density functional theory(DFT)calculations indicate that the enhanced catalytic performance of MnCeO_(x)can be traced back to its“Mn–OL(VÖ)–Mn–OL(VÖ)–Ce”connectivities.The Mn dopant strongly facilitates the formation of surface oxygen vacancies(VÖ)by liberating surface lattice oxygen(OL)via CO*+OL→CO_(2)*+VÖand promotes the reduction of NO,according to NO*+VÖ→N*+OL and 2N*→N_(2).The Mn dopant impact on both the adsorption of CO and activation of OL reveals that a balance between these two effects is critical for facilitating all reaction steps. 展开更多
关键词 NO reduction with CO manganese-ceria solid solution morphology effects reaction mechanism active sites
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A Hospital-Based Study on Congenital Heart Defects—Haidian District,Beijing Municipality,China,2013–2022
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作者 Yaxian Wu Chao Meng +2 位作者 Jufen liu Yuan Wei zhiwen li 《China CDC weekly》 SCIE CSCD 2023年第36期809-814,共6页
Summary What is already known about this topic?Congenital heart defects(CHDs)represent the most prevalent birth defects in China,exhibiting significant mortality and morbidity rates.Recent years have witnessed a stead... Summary What is already known about this topic?Congenital heart defects(CHDs)represent the most prevalent birth defects in China,exhibiting significant mortality and morbidity rates.Recent years have witnessed a steady increase in the occurrence of CHDs,highlighting a crucial need for rigorous research focus. 展开更多
关键词 CONGENITAL MORTALITY rigorous
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Periconceptional Folic Acid Use and Its Effects on Neural Tube Defects—Five Counties,Shanxi Province,China,2010–2016
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作者 Yali Zhang Jufen liu +2 位作者 Le Zhang Lei Jin zhiwen li 《China CDC weekly》 SCIE CSCD 2023年第36期804-808,共5页
Summary What is already known about this topic?Robust evidence indicates that supplementing with folic acid periconceptionally may decrease the risk of neural tube defects(NTDs)in fetuses.What is added by this report?... Summary What is already known about this topic?Robust evidence indicates that supplementing with folic acid periconceptionally may decrease the risk of neural tube defects(NTDs)in fetuses.What is added by this report?Over half of the mothers in both the NTD case group and the control group utilized folic acid supplements during the periconceptional period,showing no notable variations between the two groups. 展开更多
关键词 utilized MOTHER CONCEPTION
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Effects of Short Interpregnancy Intervals on Adverse Pregnancy Outcomes—Haidian District,Beijing Municipality,China,2017–2019
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作者 Yuan li Suhong Gao +5 位作者 Jiamei Wang Hang An Le Zhang Yali Zhang Xiaohong liu zhiwen li 《China CDC weekly》 SCIE CSCD 2023年第35期767-772,I0001,共7页
Summary What is already known about this topic?Interpregnancy intervals(IPIs)that are either excessively long or short have been linked with an elevated risk of adverse perinatal outcomes.Presently,no pertinent guidel... Summary What is already known about this topic?Interpregnancy intervals(IPIs)that are either excessively long or short have been linked with an elevated risk of adverse perinatal outcomes.Presently,no pertinent guidelines have been established in China to provide clear direction with regard to optimal IPI.What is added by this report?A brief interpregnancy interval may elevate the risk of miscarriage,postpartum hemorrhage,and fetal distress among expectant women.What are the implications for public health practice? 展开更多
关键词 PREGNANCY ELEVATED DISTRESS
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Trends in the Prevalence of Births with Chromosomal Abnormalities—Haidian District,Beijing Municipality,China,2013–2022
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作者 Shuangbo Xia Chao Meng +5 位作者 Xiao Cheng Duoduo Wang Yaxian Wu zhiwen li Yuan Wei Jufen liu 《China CDC weekly》 SCIE CSCD 2023年第36期791-796,共6页
Summary What is already known about this topic?The primary causes of early miscarriage and stillbirth are chromosomal abnormalities(CAs)whose prevalence has been observed to increase in recent years.What is added by t... Summary What is already known about this topic?The primary causes of early miscarriage and stillbirth are chromosomal abnormalities(CAs)whose prevalence has been observed to increase in recent years.What is added by this report?According to data received from a hospital-based birthdefect surveillance system in the Haidian District,Beijing,there was a significant increase in the prevalence of CAs along with most subtypes from 2013 to 2022. 展开更多
关键词 BEIJING DISTRICT BIRTH
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Periconceptional Folic Acid Only Versus Multiple Micronutrients Containing Folic Acid and Association with Gestational Diabetes Mellitus-Beijing Municipality,China,2017-2021
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作者 Shuangbo Xia Yushan Du +6 位作者 Ziyang Ren Jinjuan Zhang Suhong Gao Jiamei Wang zhiwen li Xiaohong liu Jufen liu 《China CDC weekly》 SCIE CSCD 2023年第23期505-510,共6页
Summary What is already known about this topic?Inconsistent results have been reported on the association between periconceptional folic acid only(FAO)or multiple micronutrients containing folic acid(MMFA)supplementat... Summary What is already known about this topic?Inconsistent results have been reported on the association between periconceptional folic acid only(FAO)or multiple micronutrients containing folic acid(MMFA)supplementation and the risk of gestational diabetes mellitus(GDM)in previous research.What is added by this report?In a prospective cohort study conducted among pregnant women in Haidian District,Beijing Municipality,it was observed that those who took MMFA demonstrated a higher likelihood of developing GDM in comparison to those who consumed FAO periconceptionally.Interestingly,the increased risk for GDM in pregnant women supplemented with MMFA compared to FAO was primarily due to changes in fasting plasma glucose.What are the implications for public health practice?It is highly recommended that women prioritize the use of FAO in order to yield potential benefits in the prevention of GDM. 展开更多
关键词 prevention DIABETES CONCEPTION
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Surface ligand engineering on the optical properties of atomically precise AuAg nanoclusters
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作者 Xiang liu Yifei Zhang +2 位作者 zhiwen li Gao li Farid Taherkhani 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2023年第9期1-5,共5页
1.Introduction In recent decade,atomically precise metal nanoclusters,comprised of metal kernel and surface protecting ligands,have appeared as a new and promising nanomaterial for abundant applications,such as nanoca... 1.Introduction In recent decade,atomically precise metal nanoclusters,comprised of metal kernel and surface protecting ligands,have appeared as a new and promising nanomaterial for abundant applications,such as nanocatalysis,sensor,photoluminescence,a few to name,which is attributed to their electron energy quantization arising from quantum size effect[1].And the very recent investigations showed that the configuration of metal kernel and the electronic properties of metal nanoclusters with the same metal core are largely affected by the surface protecting ligands[[2],[3]].For example,the surface ligands can significantly alter the catalytic performance of metal nanocluster catalysts(e.g.activity and selectivity)in a positive way.We have found that the Au_(25)(SR)_(18)nanocluster with the aromatic ligands can give higher conversions and a markedly increasing selectivity toward the desired product[4]. 展开更多
关键词 PRECISE CLUSTERS SELECTIVITY
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The evolution of robotics:research and application progress of dental implant robotic systems
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作者 Chen liu Yuchen liu +3 位作者 Rui Xie zhiwen li Shizhu Bai Yimin Zhao 《International Journal of Oral Science》 SCIE CAS 2024年第2期173-185,共13页
The use of robots to augment human capabilities and assist in work has long been an aspiration.Robotics has been developing since the 1960s when the first industrial robot was introduced.As technology has advanced,rob... The use of robots to augment human capabilities and assist in work has long been an aspiration.Robotics has been developing since the 1960s when the first industrial robot was introduced.As technology has advanced,robotic-assisted surgery has shown numerous advantages,including more precision,efficiency,minimal invasiveness,and safety than is possible with conventional techniques,which are research hotspots and cutting-edge trends.This article reviewed the history of medical robot development and seminal research papers about current research progress.Taking the autonomous dental implant robotic system as an example,the advantages and prospects of medical robotic systems would be discussed which would provide a reference for future research. 展开更多
关键词 robot robotic application
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Monolithic integration of MoS2-based visible detectors and GaN-based UV detectors 被引量:4
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作者 YOU WU zhiwen li +7 位作者 KAH-WEE ANG YUPING JIA ZHIMING SHI ZHI HUANG WENJIE YU XIAOJUAN SUN XINKE liU DABING li 《Photonics Research》 SCIE EI CSCD 2019年第10期1127-1133,共7页
With the increasing demand for high integration and multi-color photodetection for both military and civilian applications, the research of multi-wavelength detectors has become a new research hotspot. However, curren... With the increasing demand for high integration and multi-color photodetection for both military and civilian applications, the research of multi-wavelength detectors has become a new research hotspot. However, current research has been mainly in visible dual-or multi-wavelength detectors, while integration of both visible light and ultraviolet(UV) dual-wavelength detectors has rarely been studied. In this work, large-scale and high-quality monolayer MoS2 was grown by the chemical vapor deposition method on transparent free-standing GaN substrate. Monolithic integration of MoS2-based visible detectors and GaN-based UV detectors was demonstrated using common semiconductor fabrication technologies such as photolithography, argon plasma etching, and metal deposition. High performance of a 280 nm and 405 nm dual-wavelength photodetector was realized.The responsivity of the UV detector reached 172.12 A/W, while that of the visible detector reached 17.5 A/W.Meanwhile, both photodetectors achieved high photocurrent gain, high external quantum efficiency, high normalized detection rate, and low noise equivalent power. Our study extends the future application of dual-wavelength detectors for image sensing and optical communication. 展开更多
关键词 VISIBLE INTEGRATION ULTRAVIOLET
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Prevalence of Metabolic Syndrome and Risk Factors Among Chinese Adults:Results from a Population-Based Study—Beijing,China,2017–2018 被引量:5
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作者 Jufen liu Qingping liu +13 位作者 zhiwen li Jing Du Chao Wang Yanlin Gao Zaihua Wei Jing Wang Yunping Shi Jianting Su Yang liu Ping Wang Chunyan Xie Gang li Bing Shao Le Zhang 《China CDC weekly》 2022年第29期640-645,共6页
Summary What is already known about this topic?Metabolic syndrome(MetS)is one of the most easily available health indicative markers for cardiovascular diseases,and it has become a major public health problem worldwid... Summary What is already known about this topic?Metabolic syndrome(MetS)is one of the most easily available health indicative markers for cardiovascular diseases,and it has become a major public health problem worldwide due to increasing urbanization and aging populations.The prevalence of MetS increased dramatically in China,however,there are no records of MetS defined by the 2017 Chinese Diabetes Society for Beijing by far.What is added by this report?In this study,the data of 24,412 participants aged 18–74 years from a large population-based study in Beijing was collected.The overall prevalence of MetS among Beijing residents was 24.5%.The prevalence was 35.2%in males and 15.4%in females.What are the implications for public health practice?Effective public health strategies should target males,people with older age,lower education,higher body mass index,smokers,those who drink alcohol,those who are unemployed or retired,and those who live in rural areas on MetS prevention and control. 展开更多
关键词 METABOLIC PREVENTION SMOKE
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Strain enhancement for a MoS2-on-GaN photodetector with an Al2O3 stress liner grown by atomic layer deposition 被引量:1
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作者 zhiwen li JIANGliU LUO +4 位作者 SHENGQUN HU QIANG liU WENJIE Yu YOUMING LU XINKE liU 《Photonics Research》 SCIE EI CSCD 2020年第6期799-805,共7页
Strain regulation as an effective way to enhance the photoelectric properties of two dimensional(2D)transition metal dichalcogenides has been widely employed to improve the performance of photovoltaic devices.In this ... Strain regulation as an effective way to enhance the photoelectric properties of two dimensional(2D)transition metal dichalcogenides has been widely employed to improve the performance of photovoltaic devices.In this work,tensile strain was introduced in multilayer MoS2 grown on GaN by depositing 3 nm of Al2O3 on the surface.The temperature dependent Raman spectrum shows that the thermal stability of MoS2 is improved by Al2O3.Theoretical simulations confirmed the existence of tensile strain on MoS2 covered with Al2O3,and the bandgap and electron effective mass of six layers of MoS2 decreased due to tensile strain,which resulted in an increase of electron mobility.Due to the tensile strain ffect,the photodetector with the Al2O3 stress liner achieved better performance under the illumination of 365 nm wavelength,including a higher responsivity of 24.6 A/W,photoconductive gain of 520,and external quantum fficiency of 8381%,which are more than twice the corresponding values of photodetectors without Al2O3.Our work provides an effective technical way for improving the performance of 2D material photodetectors. 展开更多
关键词 STRESS ILLUMINATION layer
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