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Association between Residential Greenness and Cardiometabolic Risk Factors among Adults in Rural Xinjiang Uygur Autonomous Region,China:A Cross-Sectional Study
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作者 Leyao Jian Bo Yang +10 位作者 Rulin Ma Shuxia guo Jia He Yu Li Yusong Ding Dongsheng Rui Yidan Mao Xin He Xueying Sun Shengyu Liao heng guo 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第10期1184-1194,共11页
Objective This study aimed to explore the relationships between residential greenness and cardiometabolic risk factors among rural adults in Xinjiang Uygur Autonomous Region(Xinjiang)and thus provide a theoretical bas... Objective This study aimed to explore the relationships between residential greenness and cardiometabolic risk factors among rural adults in Xinjiang Uygur Autonomous Region(Xinjiang)and thus provide a theoretical basis and data support for improving the health of residents in this region.Methods We recruited 9,723 adult rural residents from the 51st Regiment of the Third Division of the Xinjiang Production and Construction Corps in September 2016.The normalized difference vegetation index(NDVI)was used to estimate residential greenness.The generalized linear mixed model(GLMM)was used to examine the association between residential greenness and cardiometabolic risk factors.Results Higher residential greenness was associated with lower cardiometabolic risk factor prevalence.After adjustments were made for age,sex,education,and marital status,for each interquartile range(IQR)increase of NDVI500-m,the risk of hypertension was reduced by 10.3%(OR=0.897,95%CI=0.836-0.962),the risk of obesity by 20.5%(OR=0.795,95%CI=0.695-0.910),the risk of type 2 diabetes by 15.1%(OR=0.849,95%CI=0.740-0.974),and the risk of dyslipidemia by 10.5%(OR=0.895,95%CI=0.825-0.971).Risk factor aggregation was reduced by 20.4%(OR=0.796,95%CI=0.716-0.885)for the same.Stratified analysis showed that NDVI500-m was associated more strongly with hypertension,dyslipidemia,and risk factor aggregation among male participants.The association of NDVI500-m with type 2 diabetes was stronger among participants with a higher education level.PM10 and physical activity mediated 1.9%-9.2%of the associations between NDVI500-m and obesity,dyslipidemia,and risk factor aggregation.Conclusion Higher residential greenness has a protective effect against cardiometabolic risk factors among rural residents in Xinjiang.Increasing the area of green space around residences is an effective measure to reduce the burden of cardiometabolic-related diseases among rural residents in Xinjiang. 展开更多
关键词 Green space Cardiometabolic risk factors Cross-sectional study Rural adults
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Exploring plasmons weakly coupling to perovskite excitons with tunable emission by energy transfer
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作者 严国栋 张振华 +5 位作者 郭衡 陈金平 蒋青松 崔乾楠 石增良 徐春祥 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期537-544,共8页
Localized surface plasmon resonance(LSPR) has caused extensive concern and achieved widespread applications in optoelectronics. However, the weak coupling of plasmons and excitons in a nanometal/semiconductor system r... Localized surface plasmon resonance(LSPR) has caused extensive concern and achieved widespread applications in optoelectronics. However, the weak coupling of plasmons and excitons in a nanometal/semiconductor system remains to be investigated via energy transfer. Herein, bandgap tunable perovskite films were synthesized to adjust the emission peaks,for further coupling with stable localized surface plasmons from gold nanoparticles. The degree of mismatch, using steadystate and transient photoluminescence(PL), was investigated systematically in two different cases of gold nanoparticles that were in direct contacting and insulated. The results demonstrated the process of tuning emission coupled to LSPR via wavelength-dependent photoluminescence intensity in the samples with an insulating spacer. In the direct contact case,the decreased radiative decay rate involves rapid plasmon resonance energy transfer to the perovskite semiconductor and non-radiative energy transfer to metal nanoparticles in the near-field range. 展开更多
关键词 PLASMONS photoluminescence tunable emission PEROVSKITE
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Effects of electron temperature on the ion extraction characteristics in a decaying plasma confined between two parallel plates
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作者 Jian CHEN Tianzuo FU +3 位作者 heng guo Heping LI Dongjun JIANG Mingsheng ZHOU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第4期99-106,共8页
In this paper,a one-dimension particle-in-cell(PIC)code(EDIPIC)is employed to simulate the parallel-plate ion extraction process under an externally applied electrostatic field,focusing on the analysis of the influe n... In this paper,a one-dimension particle-in-cell(PIC)code(EDIPIC)is employed to simulate the parallel-plate ion extraction process under an externally applied electrostatic field,focusing on the analysis of the influe nee of the initial electron temperature on the extracted ion fluxes to the metal plates during the ion extraction process.Compared with previously published results,the plasma oscillations on a timescale of the electron plasma period,and the excitation of the ion acoustic rarefaction waves resulting from the plasma oscillations originating from both the negative and positive electrodes,are studied for the first time.The modeling results show that both the negative and positive extractors can collect ions due to the plasma oscillations and the propagation of the ion acoustic rarefaction waves.With the in crease of the initial electron temperature achieved by keeping other parameters unchanged,on the one hand,both the ion speed and flux to the negative and positive plates increase,which leads to a significant decrease of the ion extraction time,while on the other hand,the ion flux to the positive plate after the formation of a Child-Langmuir sheath is much more sensitive to an increase of the initial electron temperature than that to the negative plate.The PIC simulation results provide a deeper physical understanding of the influence of the initial electron temperature on the characteristics of the entire ion extraction process in a decaying plasma. 展开更多
关键词 LOW-PRESSURE PLASMA decaying PLASMA SHEATH DYNAMICS
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PFNa结合钢丝环扎治疗小转子移位的不稳定型股骨转子间骨折疗效分析
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作者 郭恒 贾文杰 +1 位作者 赵际刚 杨占辉 《中国伤残医学》 2020年第7期1-3,共3页
目的:对本院伴有小转子移位的不稳定型股骨转子间骨折进行PFNa结合钢丝环扎手术的病人资料进行分析观察其治疗效果.方法:采用回顾性分析的研究方法,对本院骨科收治的2015年6月-2017年10月因外伤致伴有小转子移位的不稳定型转子间骨折行P... 目的:对本院伴有小转子移位的不稳定型股骨转子间骨折进行PFNa结合钢丝环扎手术的病人资料进行分析观察其治疗效果.方法:采用回顾性分析的研究方法,对本院骨科收治的2015年6月-2017年10月因外伤致伴有小转子移位的不稳定型转子间骨折行PFNa结合钢丝环扎手术治疗的24 例病人进行疗效分析并随访,对手术时间、术中出血量、骨折愈合时间、术后并发症进行分析;并对病人术前、术后及末次随访时的 Harris 评分、VAS 疼痛评分进行分析.结果:所有病人均顺利完成手术治疗.所有随访病人术后均获骨性愈合,愈合时间14-22 周,中位数18周, 未出现感染、内固定物失效、下肢深静脉血栓等并发症.手术时间平均(63. 50 ± 11. 50) 分钟、术中出血量平均(260. 00 ± 60) ml,按 Harris 评分、VAS 疼痛评分进行近期效果评估.术前、术后及随访末次 Harris评分为(30. 60 ± 4. 15)分(23-52分);(65. 30 ± 5. 25)分 (58-79 分);(79. 50 ± 8. 65)分(75-92分),术前、术后及末次随访 VAS 平均分(8. 26 ±0. 70)分(7-10 分);(4. 18 ± 1. 55)分(3-6 分);(1. 65 ± 2. 15)分(0-3分).术前与末次随访时 Harris评分及 VAS 评分均较前明显转优.差异有统计学意义( < 0. 05).结论:PFNa结合钢丝环扎治疗伴有小转子移位不稳定型转子间骨折力学结构合理,钢丝环扎利于维持内侧柱骨块的固定.具有可早期进行功能锻炼,保持骨折对位持久,骨折愈合好,并发症少等优点,对疼痛缓解及髋关节功能均明显改善,有利于病人尽早回归伤前生活方式. 展开更多
关键词 PFNA 钢丝环扎 股骨转子间骨折 回顾性研究
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A review of ultrafast laser micro/nano fabrication:Material processing,surface/interface controlling,and devices fabrication 被引量:2
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作者 heng guo Jiawang Xie +8 位作者 Guangzhi He Dezhi Zhu Ming Qiao Jianfeng Yan Jiachen Yu Jiaqun Li Yuzhi Zhao Ma Luo Haoze Han 《Nano Research》 SCIE EI CSCD 2024年第7期6212-6230,共19页
Ultrafast laser processing technology has offered a wide range of opportunities in micro/nano fabrication and other fields such as nanotechnology,biotechnology,energy science,and photonics due to its controllable proc... Ultrafast laser processing technology has offered a wide range of opportunities in micro/nano fabrication and other fields such as nanotechnology,biotechnology,energy science,and photonics due to its controllable processing precision,diverse processing capabilities,and broad material adaptability.The processing abilities and applications of the ultrafast laser still need more exploration.In the field of material processing,controlling the atomic scale structure in nanomaterials is challenging.Complex effects exist in ultrafast laser surface/interface processing,making it difficult to modulate the nanostructure and properties of the surface/interface as required.In the ultrafast laser fabrication of micro functional devices,the processing ability needs to be improved.Here,we review the research progress of ultrafast laser micro/nano fabrication in the areas of material processing,surface/interface controlling,and micro functional devices fabrication.Several useful ultrafast laser processing methods and applications in these areas are introduced.With various processing effects and abilities,the ultrafast laser processing technology has demonstrated application values in multiple fields from science to industry. 展开更多
关键词 ultrafast laser micro/nano fabrication material processing surface/interface controlling devices fabrication
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Mechanism of photon-induced performance changes in silicon heterojunction solar cells
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作者 Qi Deng Haoran Ye +11 位作者 Shenglei Huang Zehua Sun Yanyun Yang Lei Li Zhu Ma Rong Su Wei Long Fangdan Jiang heng guo guoqiang Xing Wenzhu Liu Jian Yu 《Science China Materials》 SCIE EI CAS CSCD 2024年第9期2873-2879,共7页
Short-wavelength ultraviolet(UV)photons adversely affect hydrogenated amorphous silicon thin films,as well as on silicon heterojunction(SHJ)solar cells and modules.This research examines the impact and mechanisms of p... Short-wavelength ultraviolet(UV)photons adversely affect hydrogenated amorphous silicon thin films,as well as on silicon heterojunction(SHJ)solar cells and modules.This research examines the impact and mechanisms of photon-induced performance changes.UV A exposure disrupts Si-H bonds,significantly reducing hydrogen content in both intrinsic and doped hydrogenated amorphous silicon(a-Si:H)films.This disruption impairs the interface passivation effect,leading to the degradation of SHJ solar cells and modules,primarily indicated by a decrease in open-circuit voltage(V_(oc))and fill factor(FF).UV irradiation from the front side of SHJ solar cells reduces V_(oc)and FF by 1.38%and 2.28%,respectively,resulting in a 2.28%efficiency decline.Cells irradiated from the backside show decreases in V_(oc)and FF of approximately 1.96%and 2.73%,respectively,leading to an overall efficiency reduction of approximately 3.58%.However,subsequent light-soaking increases V_(oc)and FF by approximately 0.96%and 1.37%,respectively,for frontside-irradiated cells,achieving an overall efficiency improvement of approximately 2.51%.Thus,light-soaking effectively recovers performance losses caused by UV irradiation in SHJ solar cells.This research clarifies the mechanisms influencing the performance of a-Si:H thin films,SHJ solar cells,and modules under UV irradiation and light-soaking,offering significant contributions towards the development of highly efficient and reliable SHJ devices. 展开更多
关键词 silicon solar cells HETEROJUNCTION UV irradiation light soaking hydrogen content
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Advances in catalysts and reaction systems for electro/photocatalytic ammonia production
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作者 Shenshen Zheng Fengying Zhang +4 位作者 Yuman Jiang Tao Xu Han Li heng guo Ying Zhou 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2024年第10期39-61,共23页
Ammonia is a vital component in the fertilizer and chemical industries, as well as serving as a significant carrier of renewable hydrogen energy. Compared with the industry’s principal technique, the Haber-Bosch meth... Ammonia is a vital component in the fertilizer and chemical industries, as well as serving as a significant carrier of renewable hydrogen energy. Compared with the industry’s principal technique, the Haber-Bosch method, for ammonia synthesis, electro/photocatalytic ammonia synthesis is increasingly recognized as a viable and eco-friendly alternative. This method enables distributed small-scale deployment and can be powered by sustainable renewable energy sources. However, the efficiency of electro/photocatalytic nitrogen reduction reaction is hindered by the challenges in activating the N≡N bond and nitrogen’s low solubility, thereby limiting its large-scale industrial applications. In this review, recent advancements in electro/photocatalytic nitrogen reduction are summarized, encompassing the complex reaction mechanisms, as well as the effective strategies for developing electro/photocatalytic catalysts and advanced reaction systems. Furthermore, the energy efficiency and economic analysis of electro/photocatalytic nitrogen fixation are deeply discussed. Finally, some unsolved challenges and potential opportunities are discussed for the future development of electro/photocatalytic ammonia synthesis. 展开更多
关键词 ammonia synthesis electro/photocatalysis nitrogen fixation reaction system economic and efficiency analysis
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Ultrafast laser processing of silk films by bulging and ablation for optical functional devices
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作者 Ming Qiao Huimin Wang +5 位作者 heng guo Ma Luo Yuzhi Zhao Haoze Han Jianfeng Yan Yingying Zhang 《Light(Advanced Manufacturing)》 2024年第3期28-38,共11页
Organic proteins are attractive owing to their unique optical properties,remarkable mechanical characteristics,and biocompatibility.Manufacturing multifunctional structures on organic protein films is essential for pr... Organic proteins are attractive owing to their unique optical properties,remarkable mechanical characteristics,and biocompatibility.Manufacturing multifunctional structures on organic protein films is essential for practical applications;however,the controllable fabrication of specific structures remains challenging.Herein,we propose a strategy for creating specific structures on silk film surfaces by modulating the bulging and ablation of organic materials.Unique surface morphologies such as bulges and craters with continuously varying diameters were generated based on the controlled ultrafast laser-induced crystal-form transition and plasma ablation of the silk protein.Owing to the anisotropic optical properties of the bulge/crater structures with different periods,the fabricated organic films can be used for large-scale inkless color printing.By simultaneously engineering bulge/crater structures,we designed and demonstrated organic film-based optical functional devices that achieves holographic imaging and optical focusing.This study provides a promising strategy for the fabrication of multifunctional micro/nanostructures that can broaden the potential applications of organic materials. 展开更多
关键词 Ultrafast laser PROTEIN BULGING Ablation Optical functional devices
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High-performance self-powered ultraviolet to near-infrared photodetector based on WS_(2)/InSe van der Waals heterostructure 被引量:4
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作者 Jinping Chen Zhen Zhang +11 位作者 Yi Ma Jiying Feng Xiaoyu Xie Xiaoxuan Wang Aoqun Jian Yuanzheng Li Zhuxin Li heng guo Yizhi Zhu Qiannan Cui Zengliang Shi Chunxiang Xu 《Nano Research》 SCIE EI CSCD 2023年第5期7851-7857,共7页
van der Waals heterostructures(vdWHs)based on two-dimensional(2D)materials without the crystal lattice matching constraint have great potential for high-performance optoelectronic devices.Herein,a WS_(2)/InSe vdWH pho... van der Waals heterostructures(vdWHs)based on two-dimensional(2D)materials without the crystal lattice matching constraint have great potential for high-performance optoelectronic devices.Herein,a WS_(2)/InSe vdWH photodiode is proposed and fabricated by precisely stacking InSe and WS_(2)flakes through an all-dry transfer method.The WS_(2)/InSe vdWH forms an n–n heterojunction with strong built-in electric field due to their intrinsic n-type semiconductor characteristics and energy-band alignments with a large Fermi level offset between WS_(2)and InSe.As a result,the device displays excellent photovoltaic behavior with a large open voltage of 0.47 V and a short-circuit current of 11.7 nA under 520 nm light illumination.Significantly,a fast rising/decay time of 63/76μs,a large light on/off ratio of 105,a responsivity of 61 mA/W,a high detectivity of 2.5×10^(11) Jones,and a broadband photoresponse ranging from ultraviolet to near-infrared(325–980 nm)are achieved at zero bias.This study provides a strategy for developing high-performance self-powered broadband photodetectors based on 2D materials. 展开更多
关键词 two-dimensional materials van der Waals heterostructure self-powered photodetector PHOTOCURRENT
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Nanoscale multi-beam lithography of photonic crystals with ultrafast laser 被引量:5
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作者 Jiaqun Li Jianfeng Yan +3 位作者 Lan Jiang Jiachen Yu heng guo Liangti Qu 《Light(Science & Applications)》 SCIE EI CSCD 2023年第8期1604-1615,共12页
Photonic crystals are utilized in many noteworthy applications like optical communications,light flow control,and quantum optics.Photonic crystal with nanoscale structure is important for the manipulation of light pro... Photonic crystals are utilized in many noteworthy applications like optical communications,light flow control,and quantum optics.Photonic crystal with nanoscale structure is important for the manipulation of light propagation in visible and near-infrared range.Herein,we propose a novel multi beam lithography method to fabricate photonic crystal with nanoscale structure without cracking.Using multi-beam ultrafast laser processing and etching,parallel channels with subwavelength gap are obtained in yttrium aluminum garnet crystal.Combining optical simulation based on Debye diffraction,we experimentally show the gap width of parallel channels can be controlled at nanoscale by changing phase holograms.With the superimposed phase hologram designing,functional structures of complicated channel arrays distribution can be created in crystal.Optical gratings of different periods are fabricated,which can diffract incident light in particular ways.This approach can efficiently manufacture nanostructures with controllable gap,and offer an alternative to the fabrication of complex photonic crystal for integrated photonics applications. 展开更多
关键词 LITHOGRAPHY BEAM OPTICS
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Portable multi-amplified temperature sensing for tumor exosomes based on MnO_(2)/IR780 nanozyme with high photothermal effect and oxidase-like activity 被引量:1
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作者 Limin Yang heng guo +2 位作者 Ting Hou Bin An Feng Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第3期226-230,共5页
Efficient determination of tumor exosomes using portable devices is crucial for the establishment of facile and convenient early cancer diagnostic methods. However, it is still challenging to effectively amplify the d... Efficient determination of tumor exosomes using portable devices is crucial for the establishment of facile and convenient early cancer diagnostic methods. However, it is still challenging to effectively amplify the detection signal to achieve tumor exosomes detection with high sensitivity by portable devices. To address this issue, we developed a portable multi-amplified temperature sensing strategy for highly sensitive detecting tumor exosomes based on multifunctional manganese dioxide/IR780 nanosheets(MnO_(2)/IR780 NSs) nanozyme with high oxidase-like activity and enhanced photothermal performance.Inspiringly, MnO_(2)/IR780 NSs were synthesized via a facile one-step method with mild experimental conditions, which not only exhibited a stronger photothermal effect than that of MnO_(2) but also showed excellent oxidase-like activity that can catalyze the oxidation of 3',3',5',5'-tetramethylbenzidine(TMB) to generate TMB oxide(oxTMB) with a robust photothermal property, thus conjoining with MnO_(2)/IR780 NSs to further enhance the temperature signal. The present assay enables highly sensitive determination of tumor exosomes with the detection limit down to 5.1×10~3 particles/mL, which was comparable or superior to those of the most previously reported sensors. Furthermore, detection of tumor exosomes spiked in biological samples was successfully realized. More importantly, our method showed the recommendable portability, robust applicability, and easy manipulation. By taking advantages of these features,this high-performance photothermal sensor offered a promising alternative means for nondestructive early cancer diagnosis and treatment efficacy evaluation. 展开更多
关键词 Synergistic signal amplification MnO_(2)/IR780 nanozyme Tumor exosomes Photothermal effect Oxidase-like activity
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三维/一维CsPbBr_(3)@PbBrOH分子矩阵高性能闪烁体
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作者 郭衡 朱益志 +6 位作者 赵庆贤 蒋青松 马懿 陈金平 宋磊 石增良 徐春祥 《Science China Materials》 SCIE EI CAS CSCD 2023年第5期2004-2012,共9页
无机卤化铅钙钛矿纳米晶体(NCs)因其优异的固有电子和光学性能成为X射线探测和成像的热门材料.然而,由于钙钛矿材料的高离子晶体结构,其存在严重的水分、热、光不稳定性问题,阻碍了其商业化.为了解决这一问题,本文从分子结构的角度设计... 无机卤化铅钙钛矿纳米晶体(NCs)因其优异的固有电子和光学性能成为X射线探测和成像的热门材料.然而,由于钙钛矿材料的高离子晶体结构,其存在严重的水分、热、光不稳定性问题,阻碍了其商业化.为了解决这一问题,本文从分子结构的角度设计了3D/1D CsPbBr_(3)@PbBrOH复合结构,将高度发光的3D CsPbBr_(3)NCs纳入1D PbBrOH基体中,形成“基体中的发射器”.制备的CsPbBr_(3)@PbBrOH在不牺牲光致发光量子产率的同时表现出优异的稳定性.同时,1D PbBrOH可以被认为是一个完美的宿主,其基体中重原子Pb的存在增强了X射线的吸收.最终,将嵌入惰性PbBrOH宿主中的发光CsPbBr_(3)NCs应用于X射线探测.CsPbBr_(3)@PbBrOH闪烁体显示出明亮的辐射发光和对X射线信号的敏感响应.此外,将闪烁体制成薄膜屏进行成像,获得了隐藏在胶囊内部的TEM网格的清晰图像且CsPbBr_(3)@PbBrOH薄膜的分辨率计算高达50 lp mm^(-1).因此,CsPbBr_(3)@PbBrOH闪烁体在电离辐射探测特别是X射线成像方面具有广阔的应用前景. 展开更多
关键词 PEROVSKITE X-ray imaging CsPbBr_(3)@PbBrOH STABILITY scintillator
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Scalability and efficiency challenges for the exascale supercomputing system:practice of a parallel supporting environment on the Sunway exascale prototype system
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作者 Xiaobin HE Xin CHEN +8 位作者 heng guo Xin LIU Dexun CHEN Yuling YANG Jie GAO Yunlong FENG Longde CHEN Xiaona DIAO Zuoning CHEN 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2023年第1期41-58,共18页
With the continuous improvement of supercomputer performance and the integration of artificial intelligence with traditional scientific computing,the scale of applications is gradually increasing,from millions to tens... With the continuous improvement of supercomputer performance and the integration of artificial intelligence with traditional scientific computing,the scale of applications is gradually increasing,from millions to tens of millions of computing cores,which raises great challenges to achieve high scalability and efficiency of parallel applications on super-large-scale systems.Taking the Sunway exascale prototype system as an example,in this paper we first analyze the challenges of high scalability and high efficiency for parallel applications in the exascale era.To overcome these challenges,the optimization technologies used in the parallel supporting environment software on the Sunway exascale prototype system are highlighted,including the parallel operating system,input/output(I/O)optimization technology,ultra-large-scale parallel debugging technology,10-million-core parallel algorithm,and mixed-precision method.Parallel operating systems and I/O optimization technology mainly support largescale system scaling,while the ultra-large-scale parallel debugging technology,10-million-core parallel algorithm,and mixed-precision method mainly enhance the efficiency of large-scale applications.Finally,the contributions to various applications running on the Sunway exascale prototype system are introduced,verifying the effectiveness of the parallel supporting environment design. 展开更多
关键词 Parallel computing Sunway Ultra-large-scale SUPERCOMPUTER
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In Situ Super-Hindrance-Triggered Multilayer Cracks for Random Lasing inπ-Functional Nanopolymer Films
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作者 Dongqing Lin Yang Li +14 位作者 He Zhang Shuai Zhang Yuezheng Gao Tianrui Zhai Shu Hu Chuanxiang Sheng heng guo Chunxiang Xu Ying Wei Shifeng Li Yelong Han Quanyou Feng Shasha Wang Linghai Xie Wei Huang 《Research》 SCIE EI CSCD 2023年第3期461-472,共12页
In situ self-assembly of semiconducting emitters into multilayer cracks is a significant solution-processing method to fabricate organic high-Q lasers.However,it is still difficult to realize from conventional conjuga... In situ self-assembly of semiconducting emitters into multilayer cracks is a significant solution-processing method to fabricate organic high-Q lasers.However,it is still difficult to realize from conventional conjugated polymers.Herein,we create the molecular super-hindrance-etching technology,based on theπ-functional nanopolymer PG-Cz,to modulate multilayer cracks applied in organic single-component random lasers.Massive interface cracks are formed by promoting interchain disentanglement with the super-steric hindrance effect ofπ-interrupted main chains,and multilayer morphologies with photonic-crystal-like ordering are also generated simultaneously during the drop-casting method.Meanwhile,the enhancement of quantum yields on micrometer-thick films(Φ=40%to 50%)ensures high-efficient and ultrastable deep-blue emission.Furthermore,a deep-blue random lasing is achieved with narrow linewidths~0.08 nm and high-quality factors Q≈5,500 to 6,200.These findings will offer promising pathways of organicπ-nanopolymers for the simplification of solution processes applied in lasing devices and wearable photonics. 展开更多
关键词 MULTILAYER LASING POLYMER
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电催化合成氨反应原位表征技术 被引量:3
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作者 杨鹏 郭恒 +2 位作者 张凤英 周莹 牛晓滨 《科学通报》 EI CAS CSCD 北大核心 2022年第24期2921-2936,共16页
常温常压下电催化氮气-水合成氨反应主要受限于氮气吸附与活化、反应路径以及析氢竞争反应.为了解析合成氨催化反应中N–N键活化和N–H键形成的作用机理,用于开发具有更高活性与更好稳定性的催化剂以提高氮气还原反应的催化选择性和氨... 常温常压下电催化氮气-水合成氨反应主要受限于氮气吸附与活化、反应路径以及析氢竞争反应.为了解析合成氨催化反应中N–N键活化和N–H键形成的作用机理,用于开发具有更高活性与更好稳定性的催化剂以提高氮气还原反应的催化选择性和氨合成效率,研究与发展实时监测催化反应过程中催化剂的结构变化和反应物种动态演变过程的原位表征技术显得至关重要.本文简介了X射线衍射、光电子能谱、吸收谱、红外光谱、拉曼光谱等多种原位表征技术在合成氨催化剂和催化反应研究的具体应用,指出用于氮气-水体系原位表征技术发展亟待解决的关键问题,并探讨了原位技术联用及时空分辨率提升所面临的挑战. 展开更多
关键词 电催化合成氨 反应机理 催化剂 催化反应 原位表征技术
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Defect passivation strategy for inorganic CsPbI2Br perovskite solar cell with a high-efficiency of 16.77% 被引量:4
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作者 Hua Zhang Jia Zhuang +8 位作者 Xingchong Liu Zhu Ma heng guo Ronghong Zheng Shuangshuang Zhao Fu Zhang Zheng Xiao Hanyu Wang Haimin Li 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第23期40-46,共7页
All-inorganic halide perovskite solar cells(PSCs)have acquired great progress,especially CsPbI2Br.However,their photoelectric conversion efficiency(PCE)remains far below the theoretical predictions.Non-radiative recom... All-inorganic halide perovskite solar cells(PSCs)have acquired great progress,especially CsPbI2Br.However,their photoelectric conversion efficiency(PCE)remains far below the theoretical predictions.Non-radiative recombination is one of the important issues affecting the photoelectric performance of the PSCs,and the defective lead ions derived from the evaporation of halide ions in the inorganic perovskite are the principal non-radiative recombination centers.Herein,the non-radiative recombination is effectively suppressed by introducing the N-methyl-2-pyrrolidone(NMP)as a Lewis base molecule to passivate the defective lead ions.Therefore,by adjusting the dosage of NMP,the smooth and pinhole-free CsPbI_(2)Br perovskite film is obtained and the optimized device exhibits a champion PCE of 16.77%with an excellent fill factor(FF)of 0.80.This work proves the effectiveness of passivation using Lewis base molecules to prevent non-radiative recombination defects in inorganic perovskite. 展开更多
关键词 All-inorganic perovskite CsPbI2Br Defect passivation Pb-O bond High PCE
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Lithocarpinols A and B,a pair of diastereomeric antineoplastic tenellone derivatives from the deep-sea derived fungus Phomopsis lithocarpus FS508 被引量:2
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作者 Jianlin Xu Haibo Tan +7 位作者 Yuchan Chen Saini Li heng guo Zilei Huang Haohua Li Xiaoxia Gao Hongxin Liu Weimin Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第2期439-442,共4页
Lithocarpinols A(1) and B(2), a pair of tenellone diastereoisomers with novel fused skeleton were isolated from the deep-sea derived fungus Phomopsis lithocarpus FS508. Their structures were elucidated by comprehensiv... Lithocarpinols A(1) and B(2), a pair of tenellone diastereoisomers with novel fused skeleton were isolated from the deep-sea derived fungus Phomopsis lithocarpus FS508. Their structures were elucidated by comprehensive spectroscopic analyses, X-ray diffraction and quantum molecular calculation. Their plausible biogenetic pathway featured an intriguing carbonyl-ene cyclization. Lithocarpinol A exhibited moderate inhibitory effect against HepG-2 and A549 tumor cell lines with IC_(50) values of 9.4 μmol/L and10.9 μmol/L,respectively. 展开更多
关键词 MARINE-DERIVED FUNGUS PHOMOPSIS lithocarpus Tenellone DERIVATIVES DIASTEREOISOMERS Cytotoxicity
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Donor strategy for promoting nonradiative decay to achieve an efficient photothermal therapy for treating cancer 被引量:2
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作者 Fei Ren Zeshun Li +8 位作者 Kai Li Xiaoyan Zheng Jianbing Shi Chen Zhang heng guo Bin Tong Lei Xi Zhengxu Cai Yuping Dong 《Science China Chemistry》 SCIE EI CSCD 2021年第9期1530-1539,共10页
Photothermal therapy(PTT)is emerging as an effective treatment for superficial carcinoma.A key challenge to the effectiveness of PTT is to develop photosensitizers with high photothermal conversion efficiency.Aiming t... Photothermal therapy(PTT)is emerging as an effective treatment for superficial carcinoma.A key challenge to the effectiveness of PTT is to develop photosensitizers with high photothermal conversion efficiency.Aiming to address this challenge,we develop a series of multi-arylpyrrole derivatives with different donors that contain different multi-rotor structures to explore highly efficient PTT photosensitizers.Among these multi-arylpyrrole derivatives,MAP4-FE nanoparticles with a small size of their donor groups and better-donating ability exhibit a high photothermal conversion efficiency(up to 72%)when they are encapsulated by an amphiphilic polymer.As a result,the MAP4-FE nanoparticles have shown satisfactory PTTeffects on in vivo tumor eradication under the guidance of photoacoustic signals.The findings of this study provide significant insights for the development of high-efficiency PTT photosensitizers for cancer treatment by making full use of the nonradiative decay of small size donors as rotors. 展开更多
关键词 aggregation-induced emission multi-arylpyrroles photothermal therapy photoacoustic imaging
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Biosynthesis of the Central Piperidine Nitrogen Heterocycle in Series a Thiopeptides 被引量:2
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作者 Jingyu Liu Zhi Lin +3 位作者 Hua Chen heng guo Jiang Tao Wen Liu 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2019年第1期35-41,共7页
Summary of main observation and conclusion Thiopeptides,arising from complex posttranslational modifications of a genetically encoded precursor peptide,are of great interest due to their structural complexity and impo... Summary of main observation and conclusion Thiopeptides,arising from complex posttranslational modifications of a genetically encoded precursor peptide,are of great interest due to their structural complexity and important biological activities.All of these antibiotics share a macrocyclic peptidyl core that contains a central,six-membered nitrogen heterocycle and are classified into five series a-e based on the oxidation state of the central nitrogenous ring.Here,we report that the biosynthesis of the central piperidine heterocycle of series a thiopeptides relies on the activity of homologues of an F420H2-dependent reductase TppX4 by exploiting and characterizing the piperidine-containing thiopeptin biosynthetic gene (tpp)cluster in Streptomyces tateyamensis.In vitro reconstruction of TppX4 activity demonstrated that the piperidine heterocycle of thiopeptins was transformed from a dehydropiperidine heterocycle,and TppX4 tolerated the changes in the C-termini and macrocyclic peptidyl core of substrate and also tolerated dehyropiperidine-containing monocyclic or bicyclic thiopeptides.The identification of TppX4 and its substrate tolerance enriches the biosynthetic toolbox for development of additional thiopeptide analogs for clinical drug screening. 展开更多
关键词 COMPLEXITY important REPORT
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