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Self-separation ionic liquid catalyst for the highly effective conversion of H_(2)S by α,β-unsaturated carboxylate esters under mild conditions
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作者 Wenjie Xiong Xiaomin Zhang +1 位作者 Xingbang Hu Youting Wu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第9期1440-1448,共9页
The deep-processing utility of pure hydrogen sulfide (H_(2)S) is a significant direction in natural gas chemical industry.Herein,a brand-new strategy of H_(2)S conversion by a,β-unsaturated carboxylate esters into th... The deep-processing utility of pure hydrogen sulfide (H_(2)S) is a significant direction in natural gas chemical industry.Herein,a brand-new strategy of H_(2)S conversion by a,β-unsaturated carboxylate esters into thiols or thioethers using task-specific carboxylate ionic liquids (ILs) as catalyst has been developed,firstly accomplishing the phase separation of product and catalyst without introducing the third component.It can be considered as a cascade reaction in which the product selectivity can be controlled by adjusting the molar ratio of H_(2)S to a,β-unsaturated carboxylate esters.Also,the effects of ILs with different anions and cations,intermittent feeding operations,as well as pressure-time kinetic behaviors on cascade reaction were investigated.Furthermore,the proposed interaction mechanism of H_(2)S conversion using butyl acrylate catalyzed by[Emim][Ac]was revealed by DFT-based theoretical calculation.The approach enables the self-phase separation promotion of catalyst and product and achieves 99%quantitative conversion under mild conditions in the absence of solvent,making the entire process ecologically benign.High-efficiency reaction activity can still be maintained after ten cycles of the catalyst.Therefore,the good results,combined with its simplicity of operation and the high recyclability of the catalyst,make this green method environmentally friendly and cost-effective.It is anticipated that this self-separation method mediated by task-specific ILs will provide a feasible strategy for H_(2)S utilization,which will guide its application on an industrial scale. 展开更多
关键词 Ionic liquid Cascade reaction self-separation H_(2)s conversion Catalysis
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Size control synthesis of sulfur doped titanium dioxide (anatase) nanoparticles,its optical property and its photo catalytic reactivity for CO_2 + H_2O conversion and phenol degradation 被引量:8
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作者 S. Tajammul Hussain Khaiber Khan R. Hussain 《Journal of Natural Gas Chemistry》 CAS CSCD 2009年第4期383-391,共9页
Sulfur doped anatase TiO2 nanoparticles (3 nm- 12 nm) were synthesized by the reaction of titanium tetrachloride, water and sulfuric acid with addition of 3 M NaOH at room temperature. The electro-optical and photoc... Sulfur doped anatase TiO2 nanoparticles (3 nm- 12 nm) were synthesized by the reaction of titanium tetrachloride, water and sulfuric acid with addition of 3 M NaOH at room temperature. The electro-optical and photocatalytic properties of the synthesized sulfur doped TiO2 nanoparticles were studied along with Degussa commercial TiO2 particles (24 nm). The results show that band gap of TiO2 particles decreases from 3.31 to 3.25 eV and for that of commercial TiO2 to 3.2 eV when the particle sizes increased from 3 nm to 12 nm with increase in sulfur doping. The results of the photocatalytic activity under UV and sun radiation show maximum phenol conversion at the particle size of 4 nm at 4.80% S-doping. Similar results are obtained using UV energy for both phenol conversion and conversion of CO2+H2O in which formation of methanol, ethanol and proponal is observed. Production of methanol is also achieved on samples with a particle size of 8 and 12 nm and sulfur doping of 4.80% and 5.26%. For TiO2 particle of 4 nm without S doping, the production of methanol, ethanol and proponal was lower as compared to the S-doped particles. This is attributed to the combined electronic effect and band gap change, S dopant, specific surface area and the light source used. 展开更多
关键词 s doped TiO2 PHOTOCATALYsT CO2 conversion phenol degradation UV IR radiation
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Multidimensional In_(2)O_(3)/In_(2)S_(3) heterojunction with lattice distortion for CO_(2) photoconversion 被引量:5
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作者 Jinman Yang Xingwang Zhu +7 位作者 Qing Yu Minqiang He Wei Zhang Zhao Mo Junjie Yuan Yuanbin She Hui Xu Huaming Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第5期1286-1294,共9页
Photocatalytic CO_(2)reduction to sustainably product of fuels is a potential route to achieve clean energy conversion.Unfortunately,the sluggish charge transport dynamics and poor CO_(2)activation performance result ... Photocatalytic CO_(2)reduction to sustainably product of fuels is a potential route to achieve clean energy conversion.Unfortunately,the sluggish charge transport dynamics and poor CO_(2)activation performance result in a low CO_(2)conversion efficiency.Herein,we develop a multidimensional In_(2)O_(3)/In_(2)S_(3)(IO/IS)heterojunction with abundant lattice distortion structure and high concentration of oxygen defects.The close contact interfaces between the junction of the two phases ensure undisturbed transmission of electrons with high‐speed.The increased free electron concentration promotes the adsorption and activation of CO2 on the catalyst surface,leaving the key intermediate*COOH at a lower energy barrier.The perfect combination of the band matching oxide and sulfide effectively reduces the internal energy barrier of the CO2 reduction reaction.Furthermore,the lattice distortion structure not only provides additional active sites,but also optimizes the kinetics of the reaction through microstructural regulation.Remarkably,the optimal IO/IS heterojunction exhibits superior CO_(2)reduction performance with CO evolution rate of 12.22μmol g^(−1)h^(−1),achieving about 4 times compared to that of In_(2)O_(3)and In2S3,respectively.This work emphasizes the importance of tight interfaces of heterojunction in improving the performance of CO_(2)photoreduction,and provides an effective strategy for construction of heterojunction photocatalysts. 展开更多
关键词 PHOTOCATALYsIs CO2 conversion In2O3/In2s3 heterojunction Interface Lattice distortion
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Construction of 2D Zn‐MOF/BiVO_(4)S‐scheme heterojunction for efficient photocatalytic CO_(2) conversion under visible light irradiation 被引量:6
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作者 Zhenlong Zhao Ji Bian +6 位作者 Lina Zhao Hongjun Wu Shuai Xu Lei Sun Zhijun Li Ziqing Zhang Liqiang Jing 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第5期1331-1340,共10页
The construction of S‐scheme heterojunction photocatalysts has been regarded as an effective avenue to facilitate the conversion of solar energy to fuel.However,there are still considerable challenges with regard to ... The construction of S‐scheme heterojunction photocatalysts has been regarded as an effective avenue to facilitate the conversion of solar energy to fuel.However,there are still considerable challenges with regard to efficient charge transfer,the abundance of catalytic sites,and extended light absorption.Herein,an S‐scheme heterojunction of 2D/2D zinc porphyrin‐based metal‐organic frameworks/BiVO_(4)nanosheets(Zn‐MOF/BVON)was fabricated for efficient photocatalytic CO_(2)conversion.The optimal one shows a 22‐fold photoactivity enhancement when compared to the previously reported BiVO4 nanoflake(ca.15 nm),and even exhibits~2‐time improvement than the traditional g‐C3N4/BiVO4 heterojunction.The excellent photoactivities are ascribed to the strengthened S‐scheme charge transfer and separation,promoted CO_(2)activation by the well‐dispersed metal nodes Zn_(2)(COO)_(4)in the Zn‐MOF,and extended visible light response range based on the results of the electrochemical reduction,electron paramagnetic resonance,and in‐situ diffuse reflectance infrared Fourier transform spectroscopy.The dimension‐matched Zn‐MOF/BVON S‐scheme heterojunction endowed with highly efficient charge separation and abundant catalytic active sites contributed to the superior CO2 conversion.This study offers a facile strategy for constructing S‐scheme heterojunctions involving porphyrin‐based MOFs for solar fuel production. 展开更多
关键词 BiVO4 nanosheet 2D zinc porphyrin‐based MOFs modification sscheme heterojunction Visible light catalysis CO_(2) conversion
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Conversion relationship of rainfall-soil moisture-groundwater in Quaternary thick cohesive soil in Jianghan Plain,Hubei Province,China 被引量:2
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作者 Tian-wen Liu Cheng Hu +4 位作者 Qing Wang Jun Li Kun Huang Zhi-hua Chen Ting-ting Shi 《China Geology》 2020年第3期462-472,共11页
The scientific field test site of rainfall-soil moisture-groundwater conversion in Dabie Mountain Area–Jianghan Plain is located in the northern region of the Jianghan Plain,the transition zone between the Dabie Moun... The scientific field test site of rainfall-soil moisture-groundwater conversion in Dabie Mountain Area–Jianghan Plain is located in the northern region of the Jianghan Plain,the transition zone between the Dabie Mountain Area and Jianghan Plain.It’s a great field test site to study the material and energy exchange among rainfall,soil moisture,and groundwater of the Earth’s critical zone in subtropical monsoon climate plain areas.This paper analyzed the connection between rainfall and volume water content(VWC)of soil at different depths of several soil profiles,and the dynamic feature of groundwater was discussed,which reveals the rainfall infiltration recharge of Quaternary Upper Pleistocene strata.The results show that the Quaternary Upper Pleistocene aquifer groundwater accepts a little direct rainfall recharge,while the lateral recharge is the main supplement source.There were 75 effective rainfall events among 120 rainfall events during the monitoring period,with an accumulated amount of 672.9 mm,and the percentages of effective rainfall amount and duration time were 62.50%and 91.56%,respectively.The max evaporation depth at the upper part in Quaternary cohesive soil was no less than 1.4 m.The soil profile was divided into four zones:(1)The sensitive zone of rainfall infiltration within 1.4 m,where the material and energy exchange frequently near the interface between atmosphere and soil;(2)the buffer zone of rainfall infiltration between 1.4 m and 3.5 m;(3)the migration zone of rainfall infiltration between 3.5 m and 5.0 m;and(4)the rainfall infiltration and groundwater level co-influenced zone below 5.0 m.The results revealed the reaction of soil moisture and groundwater to rainfall in the area covered by cohesive soil under humid climate in Earth’s critical zone,which is of great theoretical and practical significance for groundwater resources evaluation and development,groundwater environmental protection,ecological environmental improvement,drought disaster prevention,and flood disaster prevention in subtropical monsoon climate plain areas. 展开更多
关键词 Earth’s critical zone Rainfall-soil moisture-groundwater conversion Cohesive soil scientific field test site Environmental geological survey engineering Jianghan Plain Hubei Province China
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T. S. Eliot's Spiritual Journey in Designing The Cocktail Party as a Drama of Conversion
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作者 Gill Kurtulus 《Journal of Philosophy Study》 2016年第6期367-376,共10页
In his quest for spiritual fulfillment, Thomas Stearns Eliot conducts a meticulous religious study which teaches him distinctive interpretations of human existence and their various functions that they are supposed to... In his quest for spiritual fulfillment, Thomas Stearns Eliot conducts a meticulous religious study which teaches him distinctive interpretations of human existence and their various functions that they are supposed to assume in the world. Eliot's personal attachment to religious knowledge and his reflections of religious studies inevitably manifest themselves in his literary works; be it his dramas or poems, mostly in the forms of philosophical and psychoanalytical analysis of his characters and the detected problems observed in their relationships. The Cocktail Party, a play starting off as a drawing-room comedy soon converts to a serious analysis of human psychology and the nature of human interactions. While engaging with these particular points, the play offers possibilities to discuss several religious allusions, though dealt with subtly. Integrated with religion, characters' attitudes towards a given situation and their final decision position them in their quest either in "hypothetical" enlightenment or in a "supposed" repetition of a vicious circle. The enforcing power behind the play is interestingly a psychiatrist, who adds dynamism and mystery to the plot and has a special task in making the play a drama of conversion. The inner conflicts of the characters which ultimately lead to a series of problems in their relationships are the main concern which causes the characters search for different solutions. Accordingly, they make their own choices to cease their inner struggles. This paper aims to explore the concept of conversion in Eliot's The Cocktail Party with references to the playwright's religious journey in his literary career. 展开更多
关键词 T. s. Eliot drama of conversion verse drama modem poetic drama BUDDHIsM
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The role of small vessel disease in development of Alzheimer's disease 被引量:4
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作者 Marta Grau-Slevin Adria Arboix +1 位作者 John Gaffney Mark Slevin 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第4期310-320,共11页
Classically Alzheimer's disease and vascular dementia have been considered as two different entities, with their own clinical criteria, but relatively recent epidemiological and clinicopathological studies suggest an... Classically Alzheimer's disease and vascular dementia have been considered as two different entities, with their own clinical criteria, but relatively recent epidemiological and clinicopathological studies suggest an overlap between them sharing not only most of the risk factors and some clinical aspects but also pathophysiological mechanisms. Cerebrovascular lesions, especially small vessel disease (lacunar infarcts, white matter hyperintensities and microbleeds), may magnify the effects of mild Alzheimer's disease pathology and promote the progression of cognitive decline and may also be a precursor of neuronal damage and dementia. "Vascular hypothesis" of Alzheimer's disease would open a window for new approaches and treatments. 展开更多
关键词 Alzheimer's disease small vessel disease DEVELOPMENT risk factors DIAGNOsIs neuroimaging studies histopathological studies neurodegenerative disease neural regeneration
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Development of S11306+SA516Gr70 roll-bonded clad steel plate for pressure vessels 被引量:1
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作者 HOU Hong ZHANG Hanqian ZHANG Aiwen 《Baosteel Technical Research》 CAS 2017年第2期42-48,共7页
To meet the demand of the pressure vessel industry, Baosteel has developed an S11306 + SA516Gr70 roll-bonded clad steel plate. Comprehensive inspections of the composition, microstructure, and properties are performe... To meet the demand of the pressure vessel industry, Baosteel has developed an S11306 + SA516Gr70 roll-bonded clad steel plate. Comprehensive inspections of the composition, microstructure, and properties are performed to systematically evaluate the steel plate in normalized state and normalized + stress relieved state. The results show the cladding interface of the Sl1306 + SA516Gr70 roll-bonded clad steel plate has high shear strength, and the base metal has good mechanical properties. The performance is fully consistent with the technical requirements of the roll-bonded clad steel plate for pressure vessels. 展开更多
关键词 pressure vessel s 11306 sA516Gr70 roll-bonded clad steel plate normalized sR PROPERTY
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Indirect inguinal hernia containing portosystemic shunt vessel: A case report 被引量:2
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作者 Masahiro Yura Kikuo Yo +9 位作者 Asuka Hara Keita Hayashi Yuki Tajima Yasushi Kaneko Hiroto Fujisaki AkiraHirata Kiminori Takano Kumiko Hongo Kimiyasu Yoneyama Motohito Nakagawa 《World Journal of Clinical Cases》 SCIE 2021年第2期509-515,共7页
BACKGROUND Inguinal hernia repair is one of the most common general surgical operations worldwide.We present a case of indirect inguinal hernia containing an expanded portosystemic shunt vessel.CASE SUMMARY We report ... BACKGROUND Inguinal hernia repair is one of the most common general surgical operations worldwide.We present a case of indirect inguinal hernia containing an expanded portosystemic shunt vessel.CASE SUMMARY We report a 72-year-old man who had a 4 cm×4 cm swelling in the right inguinal region,which disappeared with light manual pressure.Abdominal-pelvic computed tomography(CT)revealed a right inguinal hernia containing an expanded portosystemic shunt vessel,which had been noted for 7 years due to liver cirrhosis.We performed Lichtenstein’s herniorrhaphy and identified the hernia sac as being indirect and the shunt vessel existing in the extraperitoneal cavity through the internal inguinal ring.Then,we found two short branches between the expanded shunt vessel and testicular vein in the middle part of the inguinal canal and cut these branches to allow the shunt vessel to return to the extraperitoneal cavity of the abdomen.The hernia sac was returned as well.We encountered no intraoperative complications.After discharge,groin seroma requiring puncture at the outpatient clinic was observed.CONCLUSION If an inguinal hernia patient has portal hypertension,ultrasound should be used to determine the contents of the hernia.When atypical vessels are visualized,they may be shunt vessels and additional CT is recommended to ensure the selection of an adequate approach for safe hernia repair. 展开更多
关键词 Inguinal hernia Lichtenstein’s herniorrhaphy Portosystemic shunt Portal hypertension shunt vessel Case report
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Microstructure and properties of S30403+Q345R roll-bonded clad steel plate for pressure vessels 被引量:2
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作者 HOU Hong ZHANG Hanqian JIAO Sihai 《Baosteel Technical Research》 CAS 2017年第1期40-48,共9页
To meet the demand of the domestic pressure vessel industry for roll-bonded clad steel plates, Baosteel has developed an S30403 + Q345R roll-bonded clad steel plate. Comprehensive inspections of the composition, micr... To meet the demand of the domestic pressure vessel industry for roll-bonded clad steel plates, Baosteel has developed an S30403 + Q345R roll-bonded clad steel plate. Comprehensive inspections of the composition, microstructure, and properties are made to systematically evaluate the steel plate in the normalized and normalized + stress relieved states. The results show the cladding interface of the S30403 + Q345R roll-bonded clad steel plate has high shear strength, the base metal has good properties, and the mechanical properties of the steel plate head and tail are uniform. The performance is fully consistent with the technical requirements of the roll-bonded clad steel plate for pressure vessels. 展开更多
关键词 pressure vessel s30403 Q345R roll-bonded clad steel plate normalized stress relieved PROPERTY
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“Parenchyma transection-first”strategy is superior to“tunnel-first”strategy in robotic spleen-preserving distal pancreatectomy with conservation of splenic vessels 被引量:1
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作者 Meng-Yang Li Hao-Zhe Cui +4 位作者 Jia-Ning Hao Da-Bin Xu En-Li Zhang Zhu-Zeng Yin Zhi-Ming Zhao 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2023年第6期639-644,共6页
Background: Creating a tunnel between the pancreas and splenic vessels followed by pancreatic parenchyma transection(“tunnel-first” strategy) has long been used in spleen-preserving distal pancreatectomy(SPDP) with ... Background: Creating a tunnel between the pancreas and splenic vessels followed by pancreatic parenchyma transection(“tunnel-first” strategy) has long been used in spleen-preserving distal pancreatectomy(SPDP) with splenic vessel preservation(Kimura’s procedure). However, the operation space is limited in the tunnel, leading to the risks of bleeding and difficulties in suturing. We adopted the pancreatic “parenchyma transection-first” strategy to optimize Kimura’s procedure. Methods: The clinical data of consecutive patients who underwent robotic SPDP with Kimura’s procedure between January 2017 and September 2022 at our center were retrieved. The cohort was classified into a “parenchyma transection-first” strategy(P-F) group and a “tunnel-first” strategy(T-F) group and analyzed. Results: A total of 91 patients were enrolled in this cohort, with 49 in the T-F group and 42 in the P-F group. Compared with the T-F group, the P-F group had significantly shorter operative time(146.1 ± 39.2 min vs. 174.9 ± 46.6 min, P < 0.01) and lower estimated blood loss [40.0(20.0–55.0) m L vs. 50.0(20.0–100.0) m L, P = 0.03]. Failure of splenic vessel preservation occurred in 10.2% patients in the TF group and 2.4% in the P-F group( P = 0.14). The grade 3/4 complications were similar between the two groups( P = 0.57). No differences in postoperative pancreatic fistula, abdominal infection or hemorrhage were observed between the two groups. Conclusions: The pancreatic “parenchyma transection-first” strategy is safe and feasible compared with traditional “tunnel-first strategy” in SPDP with Kimura’s procedure. 展开更多
关键词 Pancreatic parenchyma transection-first strategy Kimura’s procedure splenic vessel preservation Minimally invasive surgery
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Free Vibration Analysis of FG-CNTRC Cylindrical Pressure Vessels Resting on Pasternak Foundation with Various Boundary Conditions
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作者 Mohammad Arefi Masoud Mohammadi +1 位作者 Ali Tabatabaeian Timon Rabczuk 《Computers, Materials & Continua》 SCIE EI 2020年第3期1001-1023,共23页
This study focuses on vibration analysis of cylindrical pressure vessels constructed by functionally graded carbon nanotube reinforced composites(FG-CNTRC).The vessel is under internal pressure and surrounded by a Pas... This study focuses on vibration analysis of cylindrical pressure vessels constructed by functionally graded carbon nanotube reinforced composites(FG-CNTRC).The vessel is under internal pressure and surrounded by a Pasternak foundation.This investigation was founded based on two-dimensional elastic analysis and used Hamilton’s principle to drive the governing equations.The deformations and effective-mechanical properties of the reinforced structure were elicited from the first-order shear theory(FSDT)and rule of mixture,respectively.The main goal of this study is to show the effects of various design parameters such as boundary conditions,reinforcement distribution,foundation parameters,and aspect ratio on the free vibration characteristics of the structure. 展开更多
关键词 FG-CNTRC cylindrical pressure vessel first-ordershear deformation theory free vibration Pasternak’s foundation rule of mixture
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Uplift Resistance Calculation and Sensitive Analysis of Jack-up Wind Installation Vessels
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作者 刘志杰 刘晓宇 +1 位作者 孙德平 林成新 《Journal of Donghua University(English Edition)》 EI CAS 2016年第2期210-214,共5页
The uplift resistance calculation is an important basis for the construction decisions of the jack-up wind installation vessel and the design of the jacking system,and determines the operation risk and reliability in ... The uplift resistance calculation is an important basis for the construction decisions of the jack-up wind installation vessel and the design of the jacking system,and determines the operation risk and reliability in the installation process of the wind turbine. The influence factors of the pile shoe's penetration depth and uplift resistance are analyzed,and the calculation model and flow of the uplift resistance are given. Based on a construction example,the influence rules are analyzed for the change of the pile shoe's structural parameters on the penetration depth and uplift resistance.The analysis results show that the penetration depth is more sensitive to the width of the pile shoe,and the height has greater influence on the uplift resistance than the length and width of the spud. With the increase of the height,the uplift resistance may increase rapidly.Although the decreases of the length,width and height of the pile shoe may reduce the uplift resistance,the penetration depth may increase in the meantime. This will increase the pulling pile time and reduce the construction efficiency. So the parameters of the pile shoe should be optimized according to the adaptable geology condition so as to obtain the optimal uplift resistance and working efficiency. 展开更多
关键词 jack-up wind installation vessel uplift resistance penetration depth pile shoe’s structural parameters
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The Use of Anti-Platelet and/or Anticoagulant Agents in the Prevention of Large Vessel Vasculitis-Associated Ischemic Complications: A Meta-Analysis
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作者 James Jeong Lillian Barra 《Open Journal of Rheumatology and Autoimmune Diseases》 2014年第2期114-123,共10页
Objective: To determine the effectiveness of antiplatelet and/or anticoagulant therapy (AP/AC) at reducing ischemic events in patients with Large Vessel Vasculitis (LVV). Methods: We performed a random effects meta-an... Objective: To determine the effectiveness of antiplatelet and/or anticoagulant therapy (AP/AC) at reducing ischemic events in patients with Large Vessel Vasculitis (LVV). Methods: We performed a random effects meta-analysis of studies examining antiplatelet and/or anticoagulant therapy (AP/AC) and ischemic events in Takayasu’s Arteritis (TAK) or Giant Cell Arteritis (GCA). Severe ischemic events were defined as stroke, ischemic ocular manifestations and claudication symptoms. Any ischemic event included jaw claudication in addition to the above manifestations. Results: Seven studies met inclusion criteria: 1 TAK and 6 GCA. The majority of patients (>80%) were treated with ASA and treatment was initiated prior to diagnosis of LVV. Risk of severe and any ischemic event in patients with LVV treated with AP/AC versus no treatment was not significantly different (OR 0.570, 95% CI 0.243, 1.340 and OR 0.594, 95% CI 0.248, 1.421, respectively). For studies with follow-up data (26-76 months), AP/AC was protective for severe ischemic events (OR 0.18, 95% CI 0.04, 0.83). Findings were similar when excluding studies that did not account for potential confounders, such as cardiovascular risk factors. Conclusion: At follow-up, antiplatelet therapy significantly decreases ischemic events in patients with LVV. However, in most cases of GCA, the treatment was initiated prior to the diagnosis of vasculitis. The benefit of initiating anti-platelet therapy at the time of GCA diagnosis remains unclear. 展开更多
关键词 Giant Cell ARTERITIs Takayasu’s ARTERITIs Large vessel VAsCULITIs IsCHEMIC Aspirin ANTIPLATELET
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S型CeO_(2)/Bi_(2)MoO_(6)微球异质结的理性设计及其高效光催化CO_(2)还原
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作者 许修涛 邵春风 +2 位作者 张金锋 王中辽 代凯 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第10期39-42,共4页
人工半导体光催化CO_(2)转化被广泛认为是模拟自然碳循环的最有前途的策略之一。其中,Bi_(2)MoO_(6)具有光催化CO_(2)转化的潜力。然而,由于其光生电荷载体的快速复合,其催化性能仍然不足。因此,改善Bi_(2)MoO_(6)的催化效率是一个紧迫... 人工半导体光催化CO_(2)转化被广泛认为是模拟自然碳循环的最有前途的策略之一。其中,Bi_(2)MoO_(6)具有光催化CO_(2)转化的潜力。然而,由于其光生电荷载体的快速复合,其催化性能仍然不足。因此,改善Bi_(2)MoO_(6)的催化效率是一个紧迫的问题。在这项研究中,我们通过水热法合成了Bi_(2)MoO_(6)纳米片,并在其表面同时生长了CeO_(2)纳米颗粒,形成了Ce^(3+)/Ce^(4+)离子桥接修饰的S型异质结。时间分辨光致发光光谱和光电化学测试揭示了这种异质结的增强电荷分离效应。此外,原位X射线光电子能谱分析和理论计算进一步证实,光生电子转移路径遵循S型机制,从氧化型半导体Bi_(2)MoO_(6)的导带转移到还原型半导体CeO_(2)的价带。实验结果表明,CeO_(2)/Bi_(2)MoO_(6)、Bi_(2)MoO_(6)和CeO_(2)的光催化CO_(2)还原为CO的效率分别为65.3、14.8和1.2μmol·g^(-1)·h^(-1)。与纯Bi_(2)MoO_(6)相比,CeO_(2)/Bi_(2)MoO_(6)复合催化剂将CO_(2)光催化还原为CO的催化效率提高了3.12倍。这项工作为设计和构建新型S型异质结光催化剂提供了独特的见解。 展开更多
关键词 光催化CO_(2)转化 CeO_(2) Bi_(2)MoO_(6) s型异质结 电荷转移
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Strong Converse Inequality for the Meyer-Knig and Zeller-Durrmeyer Operators
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作者 QI QIU-LAN LIU JUAN 《Communications in Mathematical Research》 CSCD 2012年第1期1-9,共9页
In this paper we give a strong converse inequality of type B in terms of unified K-functional Kλα (f, t2) (0 ≤λ≤ 1, 0 〈 α 〈 2) for the Meyer-Knig and Zeller-Durrmeyer type operators.
关键词 Meyer-Konig and Zeller-Durrmeyer type operator moduli of smooth-ness K-functional strong converse inequality HOder's inequality
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利用电荷分离调控S型异质结光催化氧化产物选择性
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作者 谷苗莉 杨祎 +3 位作者 程蓓 张留洋 肖鹏 陈涛 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第4期185-194,共10页
半导体光催化技术为太阳能的高效利用提供了巨大的潜力.尽管众多单一半导体材料,如TiO_(2),CdS,g-C_(3)N_(4)等,已被广泛制备并用于光催化反应,但在单一光催化剂中,光生电子和空穴常因强库仑引力作用而迅速复合,导致光催化效率较低,难... 半导体光催化技术为太阳能的高效利用提供了巨大的潜力.尽管众多单一半导体材料,如TiO_(2),CdS,g-C_(3)N_(4)等,已被广泛制备并用于光催化反应,但在单一光催化剂中,光生电子和空穴常因强库仑引力作用而迅速复合,导致光催化效率较低,难以实现大规模产业化应用.针对这一问题,开发S型异质结光催化剂成为提高催化效率的有效途径之一.该异质结不仅能实现氧化还原位点在空间上的有效分离,同时保持了较强的氧化还原能力.然而,目前关于空间分离对光催化氧化产物选择性的影响研究较少.因此,深入探究S型异质结光催化剂中空间分离对产物选择性的作用机制,对于优化光催化过程、提高产物选择性具有重要意义.本文构建了具有良好暴露活性位点的2D/2D层状BiOBr/ZnIn_(2)S_(4)S型异质结(BOB/ZIS).实验发现,在纯ZnIn_(2)S_(4)体系中,由于无法实现空间上的有效电荷分离,氧还原反应(ORR)生成的H_(2)O_(2)在光生空穴的作用下进一步转化为•OH(羟基自由基),其氧化能力超过了体系中的光生空穴,导致2,5-呋喃二甲醛被过度氧化为经济性不高的产物呋喃二甲酸.在BOB/ZIS异质结中,我们实现了光生电子-空穴的有效转移和丰富的活性中心利用.ZnIn_(2)S_(4)价带上的电子通过ORR持续生成H_(2)O_(2)(1.15 mmol∙L^(-1),5 h),而BiOBr导带上的空穴则将5-羟甲基糠醛(HMF)氧化为具有高经济价值的2,5-呋喃二甲醛(有机合成中有价值的中间体).这一结果证实了S型异质结中光生电子-空穴的有效空间分离能够同时促进H_(2)O_(2)的产生和HMF的选择性氧化为2,5-呋喃二甲醛.这一发现不仅揭示了S型异质结在光催化反应中的优势,还证实了其相对于传统牺牲剂的经济可行性.原位光照X射线光电子能谱、飞秒超快瞬态吸收光谱和密度泛函理论计算均证实,在BOB/ZIS界面之间构建了S型电荷转移机制,加速了光生电子-空穴对的转移动力学.此外,通过原位傅里叶变换红外光谱研究了催化剂表面HMF氧化过程中官能团的变化,不仅加深了对纯ZnIn_(2)S_(4)体系中HMF过度氧化现象的认识,还揭示了S型异质结在选择性氧化HMF和原位生成H_(2)O_(2)中的独特光催化机制.综上所述,本文构建了2D/2D层状BiOBr/ZnIn_(2)S_(4)S型异质结,不仅实现了光生电子-空穴的有效空间分离,还提高了产物选择性和光催化效率.本文通过深入研究S型异质结在光催化反应中的作用机制,为调控光催化产物提供了新的见解,并为有机合成相关反应中S型异质结的设计提供了借鉴. 展开更多
关键词 BiOBr/ZnIn_(2)s_(4) s型异质结 过氧化氢制备 5-羟甲基糠醛选择性转化 转化机理
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基于B/S架构的空调智能监控系统设计与实现
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作者 余秋亮 王少林 王泽宇 《软件导刊》 2024年第3期114-120,共7页
为解决空调系统设备种类众多、协议不统一的问题,针对空调系统的监控需求,设计了基于分布式监控与集中管理模式、B/S架构的空调智能监控系统。首先,在设备监控层利用多线程技术实现设备实时数据的采集处理,采用多协议转换技术进行统一... 为解决空调系统设备种类众多、协议不统一的问题,针对空调系统的监控需求,设计了基于分布式监控与集中管理模式、B/S架构的空调智能监控系统。首先,在设备监控层利用多线程技术实现设备实时数据的采集处理,采用多协议转换技术进行统一协议转换、封装,将多种协议数据上传存储到数据库服务器。然后,通过模糊自适应PID控制器对监测数据进行轮询计算,调节变频器实时控制空调系统温度。最后,通过Web服务端口访问数据库服务器,实现系统集成与数据交换,建立集中控制、管理、运维的集成平台,实现系统设备的统一监控和调度,系统的统一部署和高可用性,完成空调监控系统的界面可视化并提升空调系统智能化水平。实践表明,该系统运行稳定,能实时监控空调运行状况,且具有较高的扩展性与管理效率。 展开更多
关键词 空调监控系统 B/s架构 分布式 多协议转换 模糊自适应PID
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C/S到B/S模式转换的技术研究 被引量:73
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作者 查修齐 吴荣泉 高元钧 《计算机工程》 CAS CSCD 2014年第1期263-267,共5页
随着Internet技术的兴起,致使更多的企业着手将C/S模式向B/S模式迁移。针对传统软件复用技术,对现有C/S模式的遗留系统进行分析,提出一种由C/S模式到B/S模式转换的方法。采用虚拟应用技术和.NET框架下的UIA技术,使用XML文件作为信息交... 随着Internet技术的兴起,致使更多的企业着手将C/S模式向B/S模式迁移。针对传统软件复用技术,对现有C/S模式的遗留系统进行分析,提出一种由C/S模式到B/S模式转换的方法。采用虚拟应用技术和.NET框架下的UIA技术,使用XML文件作为信息交换的载体,实现浏览器对C/S软件的远程操作,利用现有资源完成B/S结构的开发,并且无需修改源C/S软件的代码,体现模式的平台无关性,具有界面统一性、高度可扩展性以及易维护性等特征。实验结果表明,该方法在Windows XP的计算器中得到成功应用。 展开更多
关键词 C s模式 B s模式 转换 虚拟应用 UIA技术 远程操作
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Shape格式海图数据向S-57格式的转换 被引量:20
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作者 孟婵媛 翟京生 +1 位作者 陆毅 贾俊涛 《海洋测绘》 2004年第5期54-57,共4页
介绍了国际海道测量组织数字海道测量数据传输标准(IHOS 57)数据生产的国内外现状,通过对S 57数据模型和数据结构的深入研究和大量实验,实现了S 57数据的解译与生成,完成了Shape数据与S 57的格式转换。
关键词 数字海图 s-57 解译 封装 转换 目标
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