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A SYNTHETIC APPROACH FOR WATER SOLUBLE HYPERBRANCHED POLY(N,N-ETHYLIDENEBIS(N-2-CHLOROACETYL ACRYLAMIDE)) WITH HIGH DEGREE OF BRANCHING VIA ATOM TRANSFER RADICAL POLYMERIZATION/SELF-CONDENSING VINYL POLYMERIZATION 被引量:1
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作者 Li-bin Bai Rong-rong Zheng +3 位作者 Wen-liang Li Yong-gang Wu 巴信武 Hai-jun Wang 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2013年第7期1038-1045,共8页
A novel acrylamide A2B2* (A = alkene, B* = alkyl chlorine) type inimer was obtained from commercially available 1,2-ethylenediamine, chloroacetyl chloride and acryloyl chloride. The as-prepared monomer can form wa... A novel acrylamide A2B2* (A = alkene, B* = alkyl chlorine) type inimer was obtained from commercially available 1,2-ethylenediamine, chloroacetyl chloride and acryloyl chloride. The as-prepared monomer can form water-soluble hyperbranched poly(N,N-ethylidene bis(N-2-chloroacetyl acrylamide))s (HPECA) through atom transfer radical polymerization/self-condensing vinyl polymerization method in the presence alkyl chlorine/CuCl/2,2-bipyridine activation system which can effectively suppress the gelation formation.1H-NMR spectra and dual detector size exclusion chromatography proved the hyperbranched structure indisputably, and the degree of branching was determined by the detailed analyses of 1H-NMR spectra. The trend of the degree of branching was in consistent with the result of Mark- Houwink exponent a. The experiment results suggested that the conversion was 67%, Mw = 13.2 x 104, Mark-Houwink a = 0.282 and the degree of branching = 64% when the reaction temperature was 120 ℃, reaction time = 168 h and N,N- ethylidene bis(N-2-chloroacetyl acrylamide):Cu(I) = 50:0.62. 展开更多
关键词 Hyperbranched polymers Self-condensing vinyl polymerization Atom transfer radical polymerization high degree of branching Water soluble.
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VCSRA:A fast and accurate multiple sequence alignment algorithm with a high degree of parallelism
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作者 Dong Dong Wenhe Su +2 位作者 Wenqiang Shi Quan Zou Shaoliang Peng 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2018年第7期407-410,共4页
Multiple sequence alignment (MSA) is the alignment among more than two molecular biological sequences, which is a fundamental method to analyze evolutionary events such as mutations, insertions, deletions, and re-ar... Multiple sequence alignment (MSA) is the alignment among more than two molecular biological sequences, which is a fundamental method to analyze evolutionary events such as mutations, insertions, deletions, and re-arrangements. In theory, a dynamic programming algorithm can be employed to produce the optimal MSA. However, this leads to an explosive increase in computing time and memory consumption as the number of sequences increases (Taylor, 1990). So far, MSA is still regarded as one of the most challenging problems in bioinformatics and computational biology (Chatzou et al., 2016). 展开更多
关键词 VCSRA A fast and accurate multiple sequence alignment algorithm a high degree of parallelism
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Outcomes in patients with COVID-19 and new onset heart blocks: Insight from the National Inpatient Sample database
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作者 Sami J Shoura Taha Teaima +8 位作者 Muhammad Khawar Sana Ayesha Abbasi Ramtej Atluri Mahir Yilmaz Hasan Hammo Laith Ali Chanavuth Kanitsoraphan Dae Yong Park Tareq Alyousef 《World Journal of Cardiology》 2023年第9期448-461,共14页
BACKGROUND Coronavirus disease 2019(COVID-19)caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has resulted in a worldwide health crisis since it first appeared.Numerous studies demonstrated the... BACKGROUND Coronavirus disease 2019(COVID-19)caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has resulted in a worldwide health crisis since it first appeared.Numerous studies demonstrated the virus’s predilection to cardiomyocytes;however,the effects that COVID-19 has on the cardiac conduc-tion system still need to be fully understood.AIM To analyze the impact that COVID-19 has on the odds of major cardiovascular complications in patients with new onset heart blocks or bundle branch blocks(BBB).METHODS The 2020 National Inpatient Sample(NIS)database was used to identify patients admitted for COVID-19 pneumonia with and without high-degree atrioven-tricular blocks(HDAVB)and right or left BBB utilizing ICD-10 codes.The patients with pre-existing pacemakers,suggestive of a prior diagnosis of HDAVB or BBB,were excluded from the study.The primary outcome was inpatient mortality.Secondary outcomes included total hospital charges(THC),the length of hospital stay(LOS),and other major cardiac outcomes detailed in the Results section.Univariate and multivariate regression analyses were used to adjust for confounders with Stata version 17.RESULTS A total of 1058815 COVID-19 hospitalizations were identified within the 2020 NIS database,of which 3210(0.4%)and 17365(1.6%)patients were newly diagnosed with HDAVB and BBB,respectively.We observed a significantly higher odds of in-hospital mortality,cardiac arrest,cardiogenic shock,sepsis,arrythmias,and acute kidney injury in the COVID-19 and HDAVB group.There was no statistically significant difference in the odds of cerebral infarction or pulmonary embolism.Encounters with COVID-19 pneumonia and newly diagnosed BBB had a higher odds of arrythmias,acute kidney injury,sepsis,need for mechanical ventilation,and cardiogenic shock than those without BBB.However,unlike HDAVB,COVID-19 pneumonia and BBB had no significant impact on mortality compared to patients without BBB.CONCLUSION In conclusion,there is a significantly higher odds of inpatient mortality,cardiac arrest,cardiogenic shock,sepsis,acute kidney injury,supraventricular tachycardia,ventricular tachycardia,THC,and LOS in patients with COVID-19 pneumonia and HDAVB as compared to patients without HDAVB.Likewise,patients with COVID-19 pneumonia in the BBB group similarly have a higher odds of supraventricular tachycardia,atrial fibrillation,atrial flutter,ventricular tachycardia,acute kidney injury,sepsis,need for mechanical ventilation,and cardiogenic shock as compared to those without BBB.Therefore,it is essential for healthcare providers to be aware of the possible worse predicted outcomes that patients with new-onset HDAVB or BBB may experience following SARS-CoV-2 infection. 展开更多
关键词 In-patient outcomes Severe acute respiratory syndrome coronavirus 2 Coronavirus disease 2019 high degree atrioventricular blocks Bundle branch blocks Retrospective observational study
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Low-temperature-pyrolysis preparation of nanostructured graphite towards rapid potassium storage with high initial Coulombic efficiency
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作者 Jingke Ren Boyu Xing +7 位作者 Wen Luo Binyang Luo Xinfei Wu Xin Yan Wencong Feng Feiyue Wang Chaojie Cheng Liqiang Mai 《Nano Research》 SCIE EI CSCD 2024年第6期5138-5147,共10页
Industrially prepared artificial graphite(AG)is attractive for potassium-ion batteries(PIBs),but its rate performance is poor and the production process is energy intensive,so developing an efficient strategy to produ... Industrially prepared artificial graphite(AG)is attractive for potassium-ion batteries(PIBs),but its rate performance is poor and the production process is energy intensive,so developing an efficient strategy to produce novel graphite with low energy consumption and high performance is economically important.Herein,a nanostructured graphite composed of multi-walled carbon nanotubes(MWCNTs)and graphite shells was prepared by one-pot method through low-temperature pyrolysis of iron-based metal-organic framework(MOF)and carbon source.The high graphitization degree of nanostructured graphite makes the initial Coulombic efficiency(ICE)exceed 80%,and the three-dimensional(3D)conductive network ensures a specific capacity of 234 mAh·g^(−1)after 1000 cycles at a high current density of 500 mA·g^(−1).In addition,the typical graphite potassium storage mechanism is also demonstrated by in situ X-ray diffraction(XRD)and in situ Raman spectroscopy,and its practicality is also proved by the voltage of the full cells.This work provides a feasible way to optimize the practical production process of AG and expand its application in energy storage. 展开更多
关键词 graphite anode potassium-ion batteries high graphitization degree low-temperature pyrolysis initial Coulombic efficiency
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Inverse design of metasurface optical filters using deep neural network with highdegrees of freedom 被引量:2
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作者 Xiao Han Ziyang Fan +2 位作者 Zeyang Liu Chao Li L.Jay Guo 《InfoMat》 SCIE CAS 2021年第4期432-442,共11页
In order to obtain a metasurface structure capable of filtering light of a specific wavelength range in the visible band,the traditional methods usually traverse the space consisting of possible designs,searching for ... In order to obtain a metasurface structure capable of filtering light of a specific wavelength range in the visible band,the traditional methods usually traverse the space consisting of possible designs,searching for a potenti ally satisfactory structure by performing iterative calculations to solve Maxwell's equations.In this article,we propose a systematic method based on neural networks that can complete an inverse design process to solve the problem.Compared with the traditional methods,our method is much faster while competent to encom-pass a high degree of freedom to generate device structures,which can ensure that the spectra of generated structures resemble the desired ones. 展开更多
关键词 high degrees of freedom metasurface filter neural network visible band
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Toward a more open and collaborative climate change policy framework in Hong Kong and Macao within the Guangdong-Hong Kong-Macao Greater Bay Area
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作者 Coco Du Christine Loh 《Chinese Journal of Population,Resources and Environment》 2020年第3期179-187,共9页
The special administrative regions of Hong Kong and Macao enjoy a high degree of autonomy from the national policy system in devising their local policies,including measures related to climate change.Hong Kong and Mac... The special administrative regions of Hong Kong and Macao enjoy a high degree of autonomy from the national policy system in devising their local policies,including measures related to climate change.Hong Kong and Macao each have their own climate change policies,some aspects of which are more advanced than policies in China's Mainland.While their high degree of policy autonomy has advantages,this has also isolated them from China's larger environmental management and practices that continue to advance at scale.This paper reviews the climate change policies of the two special administrative regions and analyzes their strengths and innovations,particularly in adaptation.It also identifies areas where there could be closer engagement,collaboration,and capacity-building with the China's Mainland,which has the potential for greater positive impacts,especially on a regional basis. 展开更多
关键词 Climate change policy high degree of autonomy Hong Kong MACAO Guangdong-Hong Kong-Macao Greater Bay Area COLLABORATION
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The confined growth of few-layered and ultrashort-slab Ni-promoted MoS_(2)on reduced graphene oxide for deep-degree hydrodesulfurization 被引量:3
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作者 Dongxu Wang Lei Wang +6 位作者 Yanqing Jiao Aiping Wu Haijing Yan Xin Kang Chungui Tian Jiancong Liu Honggang Fu 《Nano Research》 SCIE EI CSCD 2022年第8期7052-7062,共11页
Hydrodesulfurization(HDS)is an essential process in clean fuel oil production,however,the huge challenge is the synthesis of the catalyst with plentiful active sites.Here,we have shown the design of few-layered,ultras... Hydrodesulfurization(HDS)is an essential process in clean fuel oil production,however,the huge challenge is the synthesis of the catalyst with plentiful active sites.Here,we have shown the design of few-layered,ultrashort Ni-Mo-S slabs dispersed on reduced graphene oxide(Ni-Mo-S/rGO-A)based on anchoring[PMo_(12)O_(40)]3−clusters and Ni^(2+)on polyethyleneimine(PEI)-modified graphite oxide.Structural characterizations(transmission electron microscopy(TEM),X-ray absorption fine structure(XAFS),etc.)show that Ni-Mo-S slabs with predominant monolayer and partial substitution of edge Mo atoms by isolated Ni atoms have rich accessible edge Ni-Mo-S sites and high sulfurization degree.All virtues endow it with plentiful edge-active sites,and consequently,the enhanced performance for hydrodesulfurization of dibenzothiophene(DBT).The hydrodesulfurization proceeds via a more-favorable direct desulfurization(DDS)route with a reaction rate constant(kHDS)of 48.6×10^(−7)mol·g^(−1)·s^(−1)over Ni-Mo-S/rGO-A catalyst,which is 4.3 times greater than that over traditional Ni-Mo-S/Al_(2)O_(3)catalyst and at the forefront of reported catalysts. 展开更多
关键词 few-layered Ni-promoted MoS_(2) confined growth reduced graphene oxide high sulfurization degree HYDRODESULFURIZATION
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Long-term ceramic matrix composite for aeroengine 被引量:6
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作者 Chaokun SONG Fang YE +2 位作者 Laifei CHENG Yongsheng LIU Qing ZHANG 《Journal of Advanced Ceramics》 SCIE EI CAS CSCD 2022年第9期1343-1374,共32页
Three strategies were proposed to prolong the service life of continuous fiber-reinforced silicon carbide ceramic matrix composite(CMC-SiC),which served as thermal-structure components of aeroengine at thermo-mechanic... Three strategies were proposed to prolong the service life of continuous fiber-reinforced silicon carbide ceramic matrix composite(CMC-SiC),which served as thermal-structure components of aeroengine at thermo-mechanical-oxygenic coupling environment.As for some thermal-structure components with low working stress,improving the degree of densification was crucial to prolong the service life,and the related process approaches were recited.If the thermal-structure components worked under moderate stress,the matrix cracking stress(σ^(mc))should be improved as far as possible.The fiber preform architecture,interface shear strength,residual thermal stress,and matrix strengthening were associated withσ_(mc)in this review.Introducing self-healing components was quite significant with the appearance of matrix microcracks when CMC-SiC worked at more severe environment for hundreds of hours.The damage can be sealed by glass phase originating from the reaction between self-healing components and oxygen.The effective self-healing temperature range of different self-healing components was first summarized and distinguished.The structure,composition,and preparation process of CMC-SiC should be systematically designed and optimized to achieve long duration target. 展开更多
关键词 high degree of densification matrix cracking stress SELF-HEALING DURATION silicon carbide ceramic matrix composite(CMC-SiC)
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