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晶相设计钌基纳米催化剂提高CO_(2)甲烷化活性
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作者 杨冲亚 王玮珏 +4 位作者 卓红英 沈铮 张天雨 杨小峰 黄延强 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第6期226-236,共11页
金属纳米颗粒在许多化学反应中表现出优异的催化性能,因而广泛用于能源和环境等催化领域.形貌是影响其催化行为的关键因素之一,它通过改变金属纳米颗粒表层原子排列结构,进而调控化学反应过程中的物质吸附、催化机理和反应动力学.此外,... 金属纳米颗粒在许多化学反应中表现出优异的催化性能,因而广泛用于能源和环境等催化领域.形貌是影响其催化行为的关键因素之一,它通过改变金属纳米颗粒表层原子排列结构,进而调控化学反应过程中的物质吸附、催化机理和反应动力学.此外,由于金属存在多种晶相结构,其纳米颗粒暴露的表面结构也可通过改变晶相得以实现.该调控策略可使得纳米颗粒具有独特的表面结构,并展现出不同的催化性能.因此,金属纳米颗粒的晶相设计为优化金属催化剂的催化性能提供了一种有效方式.Ru基纳米催化剂对CO_(2)甲烷化反应具有较好的活性和选择性,且密堆积的Ru(0001)晶面被证明是hcp相Ru纳米催化剂的活性中心,而(10-11)面对CO_(2)甲烷化反应的贡献较小.因此,开发具有更丰富密堆积fcc-(111)表面的Ru基纳米催化剂,有望大幅提高CO_(2)甲烷化的活性.本文首先通过密度泛函理论计算和微观动力学模拟,研究了fcc相Ru纳米催化剂的密堆积(111)晶面上CO_(2)加氢反应的催化机理.结果表明,与hcp-(0001)相比,该密堆积的fcc-(111)表面因能促进CO_(2)的吸附活化,而具有更好的CO_(2)甲烷化反应活性.制备了具有完全暴露fcc-(111)晶面的二十面体Ru金属纳米颗粒,并将其负载于惰性载体氧化铝上,结果表明,CO_(2)甲烷化活性比传统六方密堆积相(hcp)的钌基催化剂高5‒8倍,证实了fcc相催化剂具有更高的甲烷化催化性能.同时,在较高的反应温度下,fcc-晶相的Ru基催化剂在初始反应阶段甲烷化反应活性逐渐下降,但其CO_(2)甲烷化活性仍远高于hcp-相催化剂.原位X射线衍射和环境透射电镜等结果表明,在反应温度高于250°C条件下,fcc-晶相的金属催化剂发生部分晶相转变.该相变主要发生于Ru金属纳米颗粒的聚集体,并伴随着金属粒子的团聚和粒径的增长;然而,单颗粒分散的Ru纳米粒子在相同条件下仍能维持其fcc-晶相,从而确保了其较高的甲烷化活性.此外,原位红外结果进一步证实了CO_(2)甲烷化在Ru基纳米催化剂上通过氢化生成HCOO*中间体的反应路径,以及Ru纳米颗粒在反应过程中的动态结构演化.综上,金属纳米颗粒的晶相设计是调控表面原子结构及其催化反应性能的有效手段.通过对Ru基纳米催化剂的晶相设计,可以显著提升其在CO_(2)甲烷化反应中的催化活性.然而,潜在的高温晶相转变可导致催化剂活性的部分失活.总之,晶相设计通过对金属纳米粒子表面原子结构的调变,为高效催化剂的设计开发和反应机理的深入研究提供了新的机遇. 展开更多
关键词 晶相设计 面心立方相 钌纳米催化剂 二氧化碳甲烷化 相变
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肿瘤代谢标志物在肺癌液体活检中的研究进展
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作者 邹诗施 李宁 +1 位作者 张天宇 耿庆 《中国肺癌杂志》 CAS CSCD 北大核心 2024年第2期126-132,共7页
液体活检被逐渐应用于肺癌临床诊疗中。目前,随着代谢组学的发展,越来越多代谢标志物被认为是潜在的反映肿瘤发生发展的敏感标志物。本文概括了肺癌主要代谢途径的改变,包括葡萄糖代谢、氨基酸代谢、脂质代谢、鞘脂代谢、甘油磷脂代谢... 液体活检被逐渐应用于肺癌临床诊疗中。目前,随着代谢组学的发展,越来越多代谢标志物被认为是潜在的反映肿瘤发生发展的敏感标志物。本文概括了肺癌主要代谢途径的改变,包括葡萄糖代谢、氨基酸代谢、脂质代谢、鞘脂代谢、甘油磷脂代谢和嘌呤代谢。同时,本文综述了代谢标志物在肺癌早期诊断、预测疾病进展、评估化疗与免疫治疗疗效的作用,旨在为肿瘤诊疗提供有效的标志物。 展开更多
关键词 肺肿瘤 代谢标志物 液体活检 代谢组学
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K修饰MoS_(2)催化剂用于CO_(2)高选择性加氢制甲醇
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作者 杨菲菲 周维 +2 位作者 杨超然 张天雨 黄延强 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第7期58-60,共3页
在CO_(2)加氢领域,MoS_(2)催化剂表现出独特的潜力。然而MoS_(2)的边缘S空位对CH_(4)的生成更有利,这限制了目标产物甲醇的选择性。本工作中,我们发现,通过掺杂K助剂可以显著提高MoS_(2)催化CO_(2)选择性加氢制甲醇的性能,而未修饰的MoS... 在CO_(2)加氢领域,MoS_(2)催化剂表现出独特的潜力。然而MoS_(2)的边缘S空位对CH_(4)的生成更有利,这限制了目标产物甲醇的选择性。本工作中,我们发现,通过掺杂K助剂可以显著提高MoS_(2)催化CO_(2)选择性加氢制甲醇的性能,而未修饰的MoS_(2)主要产生CH_(4)。通过一系列的表征研究,我们发现,K原子更倾向于稳定在MoS_(2)的边缘位点上,并向MoS_(2)转移电子,从而增强了MoS_(2)边缘位点的碱性。这有助于CO_(2)的吸附活化,并以较低的能垒解离为CO。此外,K助剂还有助于调控CO中间体定向转化为甲醇而非CH_(4)。这一发现拓展了MoS_(2)材料在CO_(2)合成甲醇中的应用。通过掺杂K助剂,我们能够更高效地利用MoS_(2)催化CO_(2)转化为甲醇,对于减缓气候变化和开发清洁能源具有重要意义。 展开更多
关键词 CO_(2)加氢 甲醇 甲烷 选择性调控 K-MoS_(2)
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Stand biomass of Pinus sylvestris var. mongolica plantations benefits from high density monocultures in the boreal zone
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作者 Bingming Chen Shensi Liu +8 位作者 Jinghua Yu Yanqing Huang Shuai Yu Huanchu Liu tianyu zhang Xiangdong Liu Guangze Jin Wei Chen Xingyuan He 《Forest Ecosystems》 SCIE CSCD 2024年第5期650-658,共9页
Pinus sylvestris var.mongolica(P.sylvestris)plantations are extensively established in the boreal zone.Increasing stand biomass of these plantations can effectively enhance carbon stock,which is crucial for mitigating... Pinus sylvestris var.mongolica(P.sylvestris)plantations are extensively established in the boreal zone.Increasing stand biomass of these plantations can effectively enhance carbon stock,which is crucial for mitigating climate change.However,the current understanding of optimizing plantation strategies to maximize stand biomass is primarily derived from experiments in tropical and subtropical zones,which is difficult to extend to the boreal due to substantial climatic differences.Based on a comprehensive dataset from 1,076 sample plots of P.sylvestris plantations in the boreal zone of China,we evaluated the effects of tree species richness and stand density on tree height,diameter at breast height(DBH),and stand biomass to investigate the optimal plantation strategy.Furthermore,we examined how these effects changed with stand age and investigated their relative importance.We found that monocultures at a high stand density of 2,000–2,500ha^(−1) were the optimal plantation strategy to maximize stand biomass(107.5Mg·ha^(−1)),and this held true at almost all stand ages.Unfortunately,this strategy resulted in low species richness and small individual trees(10.6m height and 9.8cm DBH),thus presenting a trade-off.In addition,as stand age increased,the effect of tree species richness on stand biomass shifted from positive to negative,but the effect of stand density was always positive.Overall,stand age had the greatest effect on stand biomass,followed by stand density and then tree species richness.Our findings reveal a distinct plantation strategy for optimizing stand biomass of P.sylvestris plantations in the boreal zone.More importantly,this study highlights that(1)maximizing stand biomass in the boreal zone may compromise tree species richness;(2)net effects of tree species richness on stand biomass are not always positive,as negative selection effects offset positive complementary effects. 展开更多
关键词 Boreal forests Cold region Forestry application Mongolian Scots pine Planting strategy Tree diversity
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Parameterization, sensitivity, and uncertainty of 1-D thermodynamic thin-ice thickness retrieval
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作者 tianyu zhang Mohammed Shokr +5 位作者 Zhida zhang Fengming Hui Xiao Cheng Zhilun zhang Jiechen Zhao Chunlei Mi 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第7期93-111,共19页
Retrieval of Thin-Ice Thickness(TIT)using thermodynamic modeling is sensitive to the parameterization of the independent variables(coded in the model)and the uncertainty of the measured input variables.This article ex... Retrieval of Thin-Ice Thickness(TIT)using thermodynamic modeling is sensitive to the parameterization of the independent variables(coded in the model)and the uncertainty of the measured input variables.This article examines the deviation of the classical model’s TIT output when using different parameterization schemes and the sensitivity of the output to the ice thickness.Moreover,it estimates the uncertainty of the output in response to the uncertainties of the input variables.The parameterized independent variables include atmospheric longwave emissivity,air density,specific heat of air,latent heat of ice,conductivity of ice,snow depth,and snow conductivity.Measured input parameters include air temperature,ice surface temperature,and wind speed.Among the independent variables,the results show that the highest deviation is caused by adjusting the parameterization of snow conductivity and depth,followed ice conductivity.The sensitivity of the output TIT to ice thickness is highest when using parameterization of ice conductivity,atmospheric emissivity,and snow conductivity and depth.The retrieved TIT obtained using each parameterization scheme is validated using in situ measurements and satellite-retrieved data.From in situ measurements,the uncertainties of the measured air temperature and surface temperature are found to be high.The resulting uncertainties of TIT are evaluated using perturbations of the input data selected based on the probability distribution of the measurement error.The results show that the overall uncertainty of TIT to air temperature,surface temperature,and wind speed uncertainty is around 0.09 m,0.049 m,and−0.005 m,respectively. 展开更多
关键词 Arctic sea ice 1-D thermodynamic ice model thin-ice thickness sea ice parameterization
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Ultrasound-assisted isolation:A new method to isolate stromal vascular fraction
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作者 Yiming Gao Xiaojie zhang +5 位作者 Poh-Ching Tan Yun Xie Peiqi zhang tianyu zhang Qingfeng Li Shuangbai Zhou 《Chinese Journal of Plastic and Reconstructive Surgery》 2024年第1期8-15,共8页
Background:The stromal vascular fraction(SVF),a cluster of stem and progenitor cells isolated from adipose tissue,holds significant promise for application in regenerative medicine.However,the existing methods for SVF... Background:The stromal vascular fraction(SVF),a cluster of stem and progenitor cells isolated from adipose tissue,holds significant promise for application in regenerative medicine.However,the existing methods for SVF isolation are time-consuming and expensive.Thus,in this study,we explored a new method of SVF extrac-tion-ultrasound-assisted SVF isolation(USASI)-and compared the viability and characteristics of SVF isolated using different methods.Methods:SVF extraction methods using different combinations of ultrasound power,ultrasound time,collagenase dosage,and collagenase digestion time were compared with those of the control group(collagenase digestion method).The cell yield and vitality of the SVF were evaluated via cell counting and trypan blue staining.The cell components and immunophenotypes of freshly isolated SVF were analyzed using flow cytometry.The prolifer-ative capacity and differentiation potential of the SVF were also identified.Results:Ultrasonication at 95 W-20 kHz for 30 s followed by digestion with 0.15%collagenase for 30 min was identified as the most suitable parameter for the USASI method in isolating SVF,as recommended based on the evaluation of various tested conditions.The USASI method significantly reduced the collagenase dosage and shortened the digestion time.Compared to the collagenase digestion method,the USASI method had a higher cell yield and cell viability,with no adverse effects on cell components,proliferative capacity,or multipotential differentiation capacity.Conclusion:With reduced processing time,lower collagenase dosage,and increased cell yield without impairing the viability and characteristics of SVF,USASI holds the potential to emerge as a time-saving and cost-effective method for future clinical applications. 展开更多
关键词 Stromal vascular fractions SVF isolation Mechanical force ULTRASOUND
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Floating Production Platforms and their Applications in the Development of Oil and Gas Fields in the South China Sea 被引量:3
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作者 Dagang zhang Yongjun Chen tianyu zhang 《Journal of Marine Science and Application》 2014年第1期67-75,共9页
This paper studies the current available options for floating production platforms in developing deepwater oil fields and the potential development models of future oil and gas exploration in the South China Sea. A de... This paper studies the current available options for floating production platforms in developing deepwater oil fields and the potential development models of future oil and gas exploration in the South China Sea. A detailed review of current deepwater platforms worldwide was performed through the examples of industry projects, and the pros and cons of each platform are discussed. Four types of platforms are currently used for the deepwater development: tension leg platform, Spar, semi-submersible platform, and the floating production system offloading. Among these, the TLP and Spar can be used for dry tree applications, and have gained popularity in recent years. The dry tree application enables the extension of the drilling application for fixed platforms into floating systems, and greatly reduces the cost and complexity of the subsea operation. Newly built wet tree semi-submersible production platforms for ultra deepwater are also getting their application, mainly due to the much needed payload for deepwater making the conversion of the old drilling semi-submersible platforms impossible. These platforms have been used in different fields around the world for different environments; each has its own advantages and disadvantages. There are many challenges with the successful use of these floating platforms. A lot of lessons have been learned and extensive experience accumulated through the many project applications. Key technologies are being reviewed for the successful use of floating platforms for field development, and potential future development needs are being discussed. Some of the technologies and experience of platform applications can be well used for the development of the South China Sea oil and gas field. 展开更多
关键词 FLOATING PLATFORM DEEPWATER development OIL fielddevelopment DEEPWATER technology PLATFORM HOST
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Zwitterionic monolayer grafted ceramic membrane with an antifouling performance for the efficient oil-water separation 被引量:1
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作者 tianyu zhang Qian Wang +7 位作者 Wei Luan Xue Li Xianfu Chen Dong Ding Zhichao Shen Minghui Qiu Zhaoliang Cui Yiqun Fan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第2期227-235,共9页
Enormous demands on the separation of oil/water(O/W)emulsions in various industries,such as petrochemical,food and pharmaceutical industries,are looking for high performance and energy-efficient separation methods.Cer... Enormous demands on the separation of oil/water(O/W)emulsions in various industries,such as petrochemical,food and pharmaceutical industries,are looking for high performance and energy-efficient separation methods.Ceramic membranes have been used to deal with O/W emulsions,for its outstanding characteristics of easy-operation,high-flux,and long-term stability.However,membrane fouling is still a challenge in the industrial application of ceramic membranes.Herein,antifouling ceramic membranes were fabricated by grafting zwitterions on the membrane surface via an environment-friendly two-step grafting method,which improves the antifouling property and permeability.Successful grafting of such zwitterion on the ceramic surface was assessed by the combination of FTIR and XPS characterization.More importantly,the hydration can be formed by electrostatic interactions layer on the modified membrane,which was confirmed by TGA characterization.The antifouling performance of prepared zwitterionic ceramic membranes in the separation of O/W emulsions was systematically tested.The results suggested that zwitterion can significantly improve the flux of ceramic ultrafiltration membrane,and can also improve antifouling property dramatically by reducing the irreversible fouling in the separation of O/W emulsions.Therefore,zwitterionic ceramic membranes hold promising potentials as an antifouling,highly efficient and green method in the practical purification of the O/W emulsions. 展开更多
关键词 Ceramic membrane ZWITTERIONIC ANTI-FOULING Hydration layer Oil/water emulsion
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Risk Factors for Hemoptysis in Pulmonary Tuberculosis Patients from Southern China: A Retrospective Study 被引量:2
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作者 Shouyong Tan Danxiong Sun +5 位作者 Tiantuo zhang Yanqiong Li Yuanyuan Cao Moses M. Njire Changwei Wang tianyu zhang 《Journal of Tuberculosis Research》 2014年第4期173-180,共8页
Clinical characteristics of tuberculosis (TB) patients from southern China with pulmonary tuberculosis hemoptysis (PTH) were analyzed retrospectively in order to improve the diagnosis of TB, reduce mortality and preve... Clinical characteristics of tuberculosis (TB) patients from southern China with pulmonary tuberculosis hemoptysis (PTH) were analyzed retrospectively in order to improve the diagnosis of TB, reduce mortality and prevent the transmission of TB. A total of 1227 cases of pulmonary TB patients hospitalized in the Third Affiliated Hospital of Sun Yat-sen University and Guangzhou Chest Hospital from January to December of 2011 were analyzed retrospectively. 1) The male/female ratio of the 1227 tuberculosis cases was 2.15:1. There were 403 cases (32.8%) of PTH with a male/ female ratio of 3.03:1. 2) The ratio of patients with PTH to those with TB was designated as Rh. The Rh in the male group (36.2%, 303 cases) was higher than that in the female group (25.6%, 100 cases, risk ratio (RR) = 1.41, P ≤ 0.001). 3) The Rh in the elderly group (≥60 years old, 20.3%, 56 cases) was lower than that in the younger patients group (20 - 39 years old, 45.4%, 189 cases, RR = 2.51, P ≤ 0.001). 4) The Rh in initial treatment group (29.6%, 296 cases) was lower than that in the retreatment group (46.9%, 107 cases, RR = 1.58, P ≤ 0.001). 5) The Rh in sputum-positive TB patients (44.5%, 297 cases) was significantly higher than that in the smear-negative TB patients (18.9%, 106 cases, RR = 2.35, P ≤ 0.001). 6) The Rh of patients with lung lesions range 0.05). 7) The Rh of patients with cavities (51.8%, 309 cases) was higher than that of patients without cavities (14.9%, 94 cases, RR = 3.48, P ≤ 0.001). Male, young, retreated, sputum-positive TB patients and those with cavitary TB were more predisposed to PTH in southern China. TB patients with such characteristics should be sensitized and accorded good care. 展开更多
关键词 TUBERCULOSIS HEMOPTYSIS RISK FACTORS
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Switching CO_(2) Electroreduction Selectivity Between C_(1) and C_(2) Hydrocarbons on Cu Gas-Diffusion Electrodes 被引量:1
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作者 Jianfang zhang Zhengyuan Li +6 位作者 Rui Cai tianyu zhang Shize Yang Lu Ma Yan Wang Yucheng Wu Jingjie Wu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第2期17-25,共9页
Regulating the selectivity toward a target hydrocarbon product is still the focus of CO_(2)electroreduction.Here,we discover that the original surface Cu species in Cu gas-diffusion electrodes plays a more important r... Regulating the selectivity toward a target hydrocarbon product is still the focus of CO_(2)electroreduction.Here,we discover that the original surface Cu species in Cu gas-diffusion electrodes plays a more important role than the surface roughness,local pH,and facet in governing the selectivity toward C_(1)or C_(2)hydrocarbons.The selectivity toward C_(2)H_(4) progressively increases,while CH_(4) decreases steadily upon lowering the Cu oxidation species fraction.At a relatively low electrodeposition voltage of 1.5 V,the Cu gas-diffusion electrode with the highest Cu^(δ+)/Cu^(0)ratio favors the pathways of∗CO hydrogenation to form CH_(4) with maximum Faradaic efficiency of 65.4%and partial current density of 228 mA cm^(−2)at−0.83 V vs RHE.At 2.0 V,the Cu gas-diffusion electrode with the lowest Cu^(δ+)/Cu^(0)ratio prefers C-C coupling to form C_(2)+products with Faradaic efficiency topping 80.1%at−0.75 V vs RHE,where the Faradaic efficiency of C_(2)H_(4) accounts for 46.4%and the partial current density of C_(2)H_(4) achieves 279 mA cm^(−2).This work demonstrates that the selectivity from CH_(4) to C_(2)H_(4) is switchable by tuning surface Cu species composition of Cu gas-diffusion electrodes. 展开更多
关键词 C_(2)H_(4) CH_(4) CO_(2)electroreduction ELECTRODEPOSITION switchable selectivity
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The Influence of Pyrazinamide Monoresistance on Treatment Outcomes in Tuberculosis Patients from Southern China 被引量:2
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作者 Shouyong Tan Yunwei Rao +11 位作者 Jintao Guo Yaoju Tan Xingshan Cai Haobin Kuang Yanqiong Li Wenyan Liu Julius Mugweru Bangxing Wang Yuanyuan Cao Changwei Wang Ying zhang tianyu zhang 《Journal of Tuberculosis Research》 2016年第1期9-17,共9页
This study aimed to explore the influence of pyrazinamide (PZA) monoresistance on the treatment outcome of otherwise drug susceptible tuberculosis (TB). A cohort of 194 TB patients that were infected with strains susc... This study aimed to explore the influence of pyrazinamide (PZA) monoresistance on the treatment outcome of otherwise drug susceptible tuberculosis (TB). A cohort of 194 TB patients that were infected with strains susceptible to isoniazid (INH), rifampin (RIF) and ethambutol (EMB) were included in a retrospective study at the Guangzhou Chest Hospital. We reported 148 (76.3%) PZA- susceptible TB cases and 46 (23.7%) PZA-monoresistance TB cases identified by the BACTEC MGIT 960 system. All patients were treated with the standard 6 months WHO recommended regimen, which included 2 months of INH + RIF + EMB + PZA in the intensive-phase, and the subsequent 4 months of INH + RIF during continuation-phase. Bacterial burden in the lungs was estimated using sputum smear acid-fast bacillary count while the lung lesions and cavitations were examined by X-ray at the end of first 2 months of chemotherapy. After intensive-phase treatment, there were 164 (84.5%) cases of smear-negative conversion and 151 (77.9%) cases of total or partial lesion elimination. The rates of smear-negative conversion (78.3%) and lesion elimination (39.1%) of the PZA-monoresistant patients were similar with the PZA-sensitive group (P > 0.05). However, lung cavitation was more likely to be resolved in PZA-sensitive patients than in the PZA-patients (X2 = 9.623, P = 0.002). The smear-negative conversion rates were 95.9% for the PZA-sensitive patients and 87.0% for the PZA-monoresistant patients after 6 months of treatment (X2 = 3.461, P = 0.063). Together, our data suggest that PZA-monoresistance contributes to the delay of resolution of the lung cavitations in the Southern China population without affecting the sputum conversion and lesion elimination rates. 展开更多
关键词 TUBERCULOSIS PYRAZINAMIDE TREATMENT Monoresistance
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Surface modification of Cu_(2)O with stabilized Cu^(+) for highly efficient and stable CO_(2) electroreduction to C_(2+) chemicals
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作者 Ziyu Zhou Shuyu Liang +4 位作者 Jiewen Xiao tianyu zhang Min Li Wenfu Xie Qiang Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第9期277-285,共9页
Copper(Cu)-based materials are known as the most attractive catalysts for electrochemical carbon dioxide reduction reaction(CO_(2)RR),especially the Cu^(+) species(e.g.,Cu_(2)O),which show excellent capability for cat... Copper(Cu)-based materials are known as the most attractive catalysts for electrochemical carbon dioxide reduction reaction(CO_(2)RR),especially the Cu^(+) species(e.g.,Cu_(2)O),which show excellent capability for catalyzing CO_(2) to C_(2+) chemicals because of their unique electronic structure.However,the active Cu^(+) species are prone to be reduced to metallic Cu under an electroreduction environment,thus resulting in fast deactivation and poor selectivity.Here,we developed an advanced surface modification strategy to maintain the active Cu^(+) species via assembling a protective layer of metal-organic framework(copper benzenetricarboxylate,CuBTC) on the surface of Cu_(2)O octahedron(Cu_(2)O@CuBTC).It's encouraging to see that the Cu_(2)O@CuBTC heterostructure outperforms the bare Cu_(2)O octahedron in catalyzing CO_(2) to C_(2+) chemicals and dramatically enhances the ratio of C_(2)H_(4)/CH_(4) products.A systematic study reveals that the introduced CuBTC shell plays a critical role in maintaining the active Cu^(+) species in Cu_(2)O@CuBTC heterostructure under reductive conditions.This work offers a practical strategy for improving the catalytic performance of CO_(2)RR over copper oxides and also establishes a route to maintain the state of valence-sensitive catalysts. 展开更多
关键词 CO_(2)RR Copper Oxide Metal-organic Framework Core-shell Structure C_(2+)Chemicals
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A test of genetic divergence of a bird existing in the Sichuan Basin and its surrounding mountain ranges
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作者 Lu Wang Fangqing Liu +3 位作者 Lan Zhao Yaling Xu tianyu zhang Longying Wen 《Avian Research》 SCIE CSCD 2023年第4期553-564,共12页
Island ecosystems,serving as natural laboratories,facilitate geographical isolation,ecological specialization,and species divergence.The Sichuan Basin,surrounded by mountain ranges,represents a typical continental isl... Island ecosystems,serving as natural laboratories,facilitate geographical isolation,ecological specialization,and species divergence.The Sichuan Basin,surrounded by mountain ranges,represents a typical continental island due to its marked environmental spatial heterogeneity.This heterogeneity may contribute to geographical isolation and habitat heterogeneity,resulting in genetic divergence within populations.Therefore,we used the White-browed Laughingthrush(Garrulax sannio)as a model specimen to investigate the genetic divergence in the Sichuan Basin and its surrounding mountain ranges,given its presence in various habitats within and beyond this basin.Employing a RAD-seq dataset of 140 G.sannio individuals from 17 distinct ecological zones in the Sichuan Basin and its surrounding mountain ranges,we conducted PCA,population structure analysis,phylogenetic tree construction,and gene flow analysis to comprehensively analyze G.sannio groups.Additionally,in conjunction with geographical and ecological data,we performed isolation by distance,isolation by environment,PCA,and latent factor mixed model analysis to identify factors influencing the genetic divergence among these G.sannio groups.In summary,the 17 G.sannio groups were categorized into high-elevation,medium-elevation,and lowelevation groups.Genetic divergence in G.sannio may be attributed to both geographical distance and key ecological factors,particularly elevation and key climatic variables.Notably,the high-elevation group exhibited a greater number of SNPs and selected genes associated with the key ecological factors compared to the lowelevation group.The ADCY9 gene and several associated key pathways were identified as crucial elements driving ecological adaptation(elevation and key climatic variables)in the high-elevation group.Furthermore,climate changes during the glacial cycles may have facilitated gene flow among these groups residing in the Sichuan Basin and its surrounding mountain ranges.Our findings provide evidence of genetic divergence in G.sannio influenced by the geographical distance and key ecological factors between the Sichuan Basin and its surrounding mountain ranges.These results lay the groundwork for future research on the molecular systematics of continental islands. 展开更多
关键词 Genetic divergence Restriction site-associated DNA sequencing (RAD-seq) Sichuan Basin White-browed Laughingthrush
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Recent advances in catalytic conversion of carbon dioxide to propiolic acids over coinage-metal-based catalysts
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作者 tianyu zhang Jiawei Zhong Zhilian Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第8期572-580,I0012,共10页
The conversion of inexpensive,available C1 feedstock of carbon dioxide(CO_(2))into value-added fine chemicals via homogeneous or heterogeneous catalysis has attracted great recent interest.Coinagemetal-based(Cu,Ag,and... The conversion of inexpensive,available C1 feedstock of carbon dioxide(CO_(2))into value-added fine chemicals via homogeneous or heterogeneous catalysis has attracted great recent interest.Coinagemetal-based(Cu,Ag,and Au)catalysis has emerged as a synthetic strategy for a wide range of organic chemical reactions in past decades.In coinage-metal-catalyzed carboxylation,CO_(2)is adopted as a carboxylation reagent,while coinage-metal salts,complexes,and nanoparticles(NPs)serve as a Lewis acid catalyst to activate unsaturated chemicals,particularly alkynes.This mini-review focuses on the recent advances of coinage-metal-catalyzed carboxylation of terminal alkynes with CO_(2).Other respects,such as the role of bases,the influence of trace water,and solvent effects are also highlighted. 展开更多
关键词 Carbon dioxide Terminal alkynes Propiolic acids CATALYSIS
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High-Risk LEO Satellite Network Path Detection Based on Spatial and Temporal Delay Anomaly Analysis
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作者 tianyu zhang Hewu Li +5 位作者 Jun Liu Lu Lu Qian Wu Shaowen Zheng Zeqi Lai Yuanjie Li 《China Communications》 SCIE CSCD 2023年第7期57-71,共15页
The gradual deployment of Low-Earth Orbit(LEO)mega constellations with inter-satellite links(ISLs)promises ubiquitous,low-latency,and high-throughput satellite network services.However,networked LEO satellites with IS... The gradual deployment of Low-Earth Orbit(LEO)mega constellations with inter-satellite links(ISLs)promises ubiquitous,low-latency,and high-throughput satellite network services.However,networked LEO satellites with ISLs are also at risk of routing attacks such as hijacking.Existing defenses against route hijacking in terrestrial networks can hardly work for the LEO satellite network due to its high spatiotemporal dynamics.To deal with it,we propose RPD,a high-risk routing path detection method for LEO mega-constellation networks.RPD detects abnormal high-risk LEO network paths by checking the consistency between the path delay and the geographical distance.This is efficiently achieved by combining in-band measurements and out-of-band statistical processing to detect the anomaly of the clustering feature in the reference delay matrix.RPD avoids the recalculation of the header cryptographic marks when the handover occurs,thus greatly reducing the cost and improving the performance of highrisk path detection.Experiments showed that the proposed RPD mechanism achieves an average detection accuracy of 91.64%under normal network conditions,and maintain about 89%even when congestion occurs in multiple areas of the network and measurement noise is considered.In addition,RPD does not require any cryptographic operation on the intermediate node,only minimal communication cost with excellent scalability and deployability. 展开更多
关键词 LEO satellite networks route hijacking path verification risky path detection
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Synthesis and Evaluation of 2-Amino-4H-Pyran-3-Carbonitrile Derivatives as Antitubercular Agents
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作者 Chunxia Chen Minghui Lu +4 位作者 Zhihui Liu Junting Wan Zhengchao Tu tianyu zhang Ming Yan 《Open Journal of Medicinal Chemistry》 2013年第4期128-135,共8页
A series of 2-amino-4H-pyran-3-carbonitrile derivatives were designed and synthesized. Their antitubercular activities were evaluated against autoluminescent M. tuberculosis H37Ra and standard strain M. tuberculosis H... A series of 2-amino-4H-pyran-3-carbonitrile derivatives were designed and synthesized. Their antitubercular activities were evaluated against autoluminescent M. tuberculosis H37Ra and standard strain M. tuberculosis H37Rv. No obvious antitubercular activities could be observed (MIC > 10 ug/mL). The results are in sharp contrast with the previously reported data. 展开更多
关键词 2-Amino-4H-Pyran-3-Carbonitrile SYNTHESIS ANTITUBERCULAR Activity
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Chaff Jamming Recognition of Radar
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作者 Min Xie Shuang Zhao +2 位作者 Xiongjun Fu tianyu zhang Kaiqiang Liu 《Journal of Beijing Institute of Technology》 EI CAS 2018年第1期43-50,共8页
A modified chaff jamming recognition method of radar is investigated using grey relational analysis( GRA) based on the difference in echo correlation characteristics between a complex rigid target and chaff cloud in... A modified chaff jamming recognition method of radar is investigated using grey relational analysis( GRA) based on the difference in echo correlation characteristics between a complex rigid target and chaff cloud in time domain. Slice method( SM),a novel modeling approach,is proposed to construct an electromagnetic scattering model of chaff cloud in a scenario with slowly moving platform that is targeted. The diffusion characteristics and echo characteristics of the chaff cloud are analyzed. The GRA of a real target and chaff cloud shows that the adjacent return waves have a good correlation for the target but a weak correlation for chaff cloud. Since the correlation degree of chaff cloud's echo is far lower than that of a complex rigid target's,the chaff jamming can be identified by setting a reasonable threshold. Simulation results are presented to verify the effectiveness of this method. 展开更多
关键词 chaff jamming anti-jamming grey relational analysis radar
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Research on Development and Construction of Characteristic Town
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作者 tianyu zhang 《Journal of Architectural Research and Development》 2020年第5期10-14,共5页
Characteristic town is an innovative development model of urban-rural integration.These small towns with certain characteristics play an important role in China’s economic transformation and urban-rural integration.T... Characteristic town is an innovative development model of urban-rural integration.These small towns with certain characteristics play an important role in China’s economic transformation and urban-rural integration.Through literature search and field surveys,this article reports the existing theoretical achievements,including the conceptualization,significance of construction,and the research status of local/foreign characteristic towns.Besides,this article provides some practical suggestions towards the existing research problems and some reference for the planning and construction of characteristic towns. 展开更多
关键词 characteristic town research and review development status COUNTERMEASURES
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Pre-combustion mercury removal with co-production of hydrogen via coal electrolysis
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作者 Xiang Lyu Runming Tao tianyu zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第2期382-389,共8页
Pre-combustion mercury removal via coal electrolysis was performed and investigated on a bench-scale coal electrolytic cell(CEC)systemically,and factorial design was used to determine the effect of different operating... Pre-combustion mercury removal via coal electrolysis was performed and investigated on a bench-scale coal electrolytic cell(CEC)systemically,and factorial design was used to determine the effect of different operating conditions(coal particle size,operating temperature,operating cell voltage,and flow rate of slurry)on the percentage of mercury removal,percentage of ash removal,and dry heating value change.The results showed that the operating cell voltage,as well as the interaction between operating cell voltage and coal particle size,are significant factors in the percentage of mercury removal.There is no significant factor in the percentage of ash removal and the dry heating value change,but the coal could be purified while keeping the dry heating value almost constant after electrolysis.A co-product of hydrogen could be produced during coal electrolysis with 50%lower energy consumption compared with water electrolysis.Meanwhile,a mechanism for mercury removal in coal was proposed.The facts indicate that coal electrolysis is a promising method for precombustion mercury removal. 展开更多
关键词 Pre-combustion mercury removal Coal electrolysis Ash removal Dry heating value Hydrogen production
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Boosting oxygen vacancies by modulating the morphology of Au decorated In_(2)O_(3)with enhanced CO_(2)hydrogenation activity to CH_(3)OH
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作者 Ruxian Hou Jiewen Xiao +2 位作者 Qian Wu tianyu zhang Qiang Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第6期91-102,共12页
CO_(2)hydrogenation to methanol has become one of the most promising ways for CO_(2)utilization,however,the CO_(2)conversion rate and methanol selectivity of this reaction still need to be improved for industrial appl... CO_(2)hydrogenation to methanol has become one of the most promising ways for CO_(2)utilization,however,the CO_(2)conversion rate and methanol selectivity of this reaction still need to be improved for industrial application.Here we investigated the structure-activity relationship for CO_(2)conversion to methanol of In_(2)O_(3)-based catalysts by modulating morphology and decorating Au.Three different Au/In_(2)O_(3)catalysts were prepared,their activity follow the sequence of Au/In_(2)O_(3)-nanosphere(Au/In_(2)O_(3)-NS)>Au/In_(2)O_(3)-nanoplate(Au/In_(2)O_(3)-NP)>Au/In_(2)O_(3)-hollow microsphere(Au/In_(2)O_(3)-HM).Au/In_(2)O_(3)-NS exhibited the best performance with good CO_(2)conversion of 12.7%,high methanol selectivity of 59.8%,and large space time yield of 0.32 g CH_(3)OH/(hr·gcat)at 300℃.The high performance of Au/In_(2)O_(3)-NS was considered as the presence of Au.It contributes to the creation of more surface oxygen vacancies,which further promoted the CO_(2)adsorption and facilitated CO_(2)activation to form the formate intermediates towards methanol.This work clearly suggests that the activity of In_(2)O_(3)catalyst can be effective enhanced by structure engineering and Au decorating. 展开更多
关键词 CO_(2)hydrogenation Methanol Au/In_(2)O_(3) MORPHOLOGY Oxygen vacancies
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