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Anti-phospholipase A2 receptor-associated membranous nephropathy with human immunodeficiency virus infection treated with telitacicept:A case report
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作者 Jin-Ling wang Yan-Ling Sun +5 位作者 Zhe Kang Sheng-Kun zhang Chun-Xin Yu wan zhang Hua Xie Hong-Li Lin 《World Journal of Clinical Cases》 SCIE 2023年第22期5309-5315,共7页
BACKGROUND The co-occurrence of Anti-phospholipase A2 receptor-associated membranous nephropathy(anti-PLA2R-MN)and human immunodeficiency virus(HIV)infection is a rare clinical scenario,presenting significant challeng... BACKGROUND The co-occurrence of Anti-phospholipase A2 receptor-associated membranous nephropathy(anti-PLA2R-MN)and human immunodeficiency virus(HIV)infection is a rare clinical scenario,presenting significant challenges in terms of management and treatment.CASE SUMMARY A 32-year-old Chinese male diagnosed with HIV infection presented with a clinical history of proteinuria persisting for over two years.A kidney biopsy demonstrated subepithelial immune complex deposition and a thickened glomerular basement membrane,indicative of stage I-II membranous nephro-pathy.Immunofluorescence staining revealed granular deposition of PLA2R(3+)along the glomerular capillary loops,corroborated by a strongly positive anti-PLA2R antibody test(1:320).Initial treatment involving losartan potassium,rivaroxaban,tacrolimus,and rituximab was discontinued due to either poor effec-tiveness or the occurrence of adverse events.Following a regimen of weekly subcutaneous injections of telitacicept(160 mg),a marked decline in the 24 h urine protein was observed within a three-month period,accompanied by a rise in serum albumin level.No significant reductions in peripheral blood CD3+CD4+T and CD3+CD8+T cell counts were detected.The patient's physical and psychological conditions showed significant improvements,with no adverse events reported during the treatment course.CONCLUSION Telitacicept might offer a potential therapeutic avenue for patients diagnosed with anti-PLA2R-MN concomitant with HIV infection. 展开更多
关键词 Membranous nephropathy PLA2R Human immunodeficiency virus PROTEINURIA Telitacicept Case report
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Proximal Support Matrix Machine
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作者 wan zhang Yulan Liu 《Journal of Applied Mathematics and Physics》 2022年第7期2268-2291,共24页
In this paper, we have proposed a novel model called proximal support matrix machine (PSMM), which is mainly based on the models of proximal support vector machine (PSVM) and low rank support matrix machine (LRSMM). I... In this paper, we have proposed a novel model called proximal support matrix machine (PSMM), which is mainly based on the models of proximal support vector machine (PSVM) and low rank support matrix machine (LRSMM). In design, the PSMM model has comprehensively considered both the relationship between samples of the same class and the structure of rows or columns of matrix data. To a certain extent, our novel model can be regarded as a synthesis of the PSVM model and the LRSMM model. Since the PSMM model is an unconstrained convex problem in essence, we have established an alternating direction method of multipliers algorithm to deal with the proposed model. Finally, since a great deal of experiments on the minst digital database show that the PSMM classifier has a good ability to distinguish two digits with little difference, it encourages us to conduct more complex experiments on MIT face database, INRIA person database, the students face database and Japan female facial expression database. Meanwhile, the final experimental results show that PSMM performs better than PSVM, twin support vector machine, LRSMM and linear twin multiple rank support matrix machine in the demanding image classification tasks. 展开更多
关键词 PSMM PSVM LRSMM The Alternating Direction Method of Multipliers Al-gorithm Image Classification Tasks
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乡村振兴战略背景下建设干部学院的理论与实践研究——以红寺堡乡村振兴干部学院为例
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作者 赖一飞 张婉 +1 位作者 叶丽婷 施国弘 《教育研究前沿(中英文版)》 2021年第2期70-74,共5页
建设乡村振兴学院是贯彻实施乡村振兴战略、推动农业农村现代化的一项重要措施。本文以红寺堡乡村振兴干部学院为例,从学院建设目标与发展战略研究、学院教学组织规划、干部教育特色课程设计等三个方面具体分析了乡村振兴学院在乡村振... 建设乡村振兴学院是贯彻实施乡村振兴战略、推动农业农村现代化的一项重要措施。本文以红寺堡乡村振兴干部学院为例,从学院建设目标与发展战略研究、学院教学组织规划、干部教育特色课程设计等三个方面具体分析了乡村振兴学院在乡村振兴战略中的规划建设和作用,力争把红寺堡乡村振兴学院打造成全国领先的乡村振兴干部学院,为乡村振兴蓄势赋能。 展开更多
关键词 乡村振兴 乡村振兴干部学院 红寺堡区
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Microglia-associated neuroinflammation is a potential therapeutic target for ischemic stroke 被引量:23
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作者 wan zhang Tian Tian +4 位作者 Shao-Xin Gong Wen-Qian Huang Qin-Yi Zhou Ai-Ping wang Ying Tian 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第1期6-11,共6页
Microglia-associated neuroinflammation plays an important role in the pathophysiology of ischemic stroke.Microglial activation and polarization,and the inflammatory response mediated by these cells play important role... Microglia-associated neuroinflammation plays an important role in the pathophysiology of ischemic stroke.Microglial activation and polarization,and the inflammatory response mediated by these cells play important roles in the development,progression and outcome of brain injury after ischemic stroke.Currently,there is no effective strategy for treating ischemic stroke in clinical practice.Therefore,it is clinically important to study the role and regulation of microglia in stroke.In this review,we discuss the involvement of microglia in the neuroinflammatory process in ischemic stroke,with the aim of providing a better understanding of the relationship between ischemic stroke and microglia. 展开更多
关键词 brain cells central nervous system inflammation injury MACROPHAGES repair review STROKE
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Comprehensive Overview on Computational Intelligence Techniques for Machinery Condition Monitoring and Fault Diagnosis 被引量:17
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作者 wan zhang Min-Ping Jia +1 位作者 Lin Zhu Xiao-An Yan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第4期782-795,共14页
Computational intelligence is one of the most powerful data processing tools to solve complex nonlinear problems, and thus plays a significant role in intelligent fault diagnosis and prediction. However, only few com-... Computational intelligence is one of the most powerful data processing tools to solve complex nonlinear problems, and thus plays a significant role in intelligent fault diagnosis and prediction. However, only few com- prehensive reviews have summarized the ongoing efforts of computational intelligence in machinery condition moni- toring and fault diagnosis. The recent research and devel- opment of computational intelligence techniques in fault diagnosis, prediction and optimal sensor placement are reviewed. The advantages and limitations of computational intelligence techniques in practical applications are dis- cussed. The characteristics of different algorithms are compared, and application situations of these methods are summarized. Computational intelligence methods need to be further studied in deep understanding algorithm mech- anism, improving algorithm efficiency and enhancing engineering application. This review may be considered as a useful guidance for researchers in selecting a suit- able method for a specific situation and pointing out potential research directions. 展开更多
关键词 Computational intelligence Machinerycondition monitoring Fault diagnosis Neural networkFuzzy logic Support vector machine - Evolutionaryalgorithms
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引入图像信息的多模态复述生成模型
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作者 马超 万璋 +2 位作者 张玉洁 徐金安 陈钰枫 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2022年第1期45-53,共9页
在商品描述、新闻评论等多模态场景下,已有复述生成模型只能围绕文本信息生成复述。为了解决其因无法利用图像信息而导致的语义丢失问题,提出多模态复述生成模型(multi-modalityparaphrasegeneration model,MPG)来引入图像信息,并用其... 在商品描述、新闻评论等多模态场景下,已有复述生成模型只能围绕文本信息生成复述。为了解决其因无法利用图像信息而导致的语义丢失问题,提出多模态复述生成模型(multi-modalityparaphrasegeneration model,MPG)来引入图像信息,并用其生成复述。在MPG中,为了引入与原句对应的图像信息,首先根据原句构建抽象场景图,并将与原句相关联的图像区域特征转换为场景图的结点特征。进一步地,为了利用构建好的场景图来生成语义一致的复述句,使用关系图卷积神经网络和基于图的注意力机制对图结点特征进行编码和解码。在评测阶段,提出句对相似度计算方法,从MSCOCO数据集中筛选出描述图像中相同物体的句对,并将其作为复述测试集进行评测。实验结果显示,所提出的MPG模型生成的复述拥有更好的语义忠实度,表明在多模态场景下图像信息的引入对提高复述生成质量的有效性。 展开更多
关键词 复述生成 多模态 抽象场景图 注意力机制
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融合物体空间关系机制的图像摘要生成方法
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作者 万璋 张玉洁 +2 位作者 刘明童 徐金安 陈钰枫 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2021年第1期75-82,共8页
聚焦于图像中物体间位置关系这一特定信息,提出一种融合空间关系机制的神经网络图像摘要生成模型,以期为视觉问答和语音导航等下游任务提供物体方位或轨迹等关键信息。为了增强图像编码器的物体间位置关系学习能力,通过改进Transformer... 聚焦于图像中物体间位置关系这一特定信息,提出一种融合空间关系机制的神经网络图像摘要生成模型,以期为视觉问答和语音导航等下游任务提供物体方位或轨迹等关键信息。为了增强图像编码器的物体间位置关系学习能力,通过改进Transformer结构来引入几何注意力机制,显式地将物体间位置关系融合进物体外观信息中。为了辅助完成面向特定信息的抽取和摘要生成任务,进一步提出相对位置关系的数据制作方法,并基于SpatialSense数据集制作物体间位置关系的图像摘要数据集Re-Position。与5个典型模型的对比测评实验结果表明,所提模型的5个指标在公开测试集COCO上优于其他模型,全部6个指标在本文制作的Re-Position数据集上优于其他模型。 展开更多
关键词 图像摘要 物体间位置关系 注意力机制 Transformer结构
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Simultaneous CO_(2) capture and thermochemical heat storage by modified carbide slag in coupled calcium looping and CaO/Ca(OH)2 cycles 被引量:6
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作者 Chunxiao zhang Yingjie Li +2 位作者 Zhiguo Bian wan zhang Zeyan wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第8期76-85,共10页
The simultaneous CO_(2) capture and heat storage performances of the modified carbide slag with byproduct of biodiesel were investigated in the process coupled calcium looping and CaO/Ca(OH)2 thermochemical heat stora... The simultaneous CO_(2) capture and heat storage performances of the modified carbide slag with byproduct of biodiesel were investigated in the process coupled calcium looping and CaO/Ca(OH)2 thermochemical heat storage using air as the heat transfer fluid.The modified carbide slag with by-product of biodiesel exhibits superior CO_(2) capture and heat storage capacities in the coupled calcium looping and heat storage cycles.The hydration conversion and heat storage density of the modified carbide slag after 30 heat storage cycles are 0.65 mol·mol^(-1) and 1.14 GJ·t^(-1),respectively,which are 1.6 times as high as those of calcined carbide slag.The negative effect of CO_(2) in air as the heat storage fluid on the heat storage capacity of the modified carbide slag is overcome by introducing CO_(2) capture cycles.In addition,the CO_(2) capture reactivity of the modified carbide slag after the multiple calcium looping cycles is enhanced by the introduction of heat storage cycles.By introducing 10 heat storage cycles after the 10th and 15th CO_(2) capture cycles,the CO_(2) capture capacities of the modified carbide slag are subsequently improved by 32%and 43%,respectively.The porous and loose structure of modified carbide slag reduces the diffusion resistances of CO_(2) and steam in the material in the coupled process.The formed CaCO_(3)in the modified carbide slag as a result of air as the heat transfer fluid in heat storage cycles decomposes to regenerate CaO in calcium looping cycles,which improves heat storage capacity.Therefore,the modified carbide slag with by-product of biodiesel seems promising in the coupled calcium looping and CaO/Ca(OH)_(2) heat storage cycles. 展开更多
关键词 Carbide slag Calcium looping CaO/Ca(OH)_(2)heat storage Modification By-product of biodiesel CO_(2)capture
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A two-stage optimization method for unmanned aerial vehicle inspection of an oil and gas pipeline network 被引量:4
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作者 Yamin Yan Yongtu Liang +4 位作者 Haoran zhang wan zhang Huixia Feng Bohong wang Qi Liao 《Petroleum Science》 SCIE CAS CSCD 2019年第2期458-468,共11页
Oil and gas pipeline networks are a key link in the coordinated development of oil and gas both upstream and downstream.To improve the reliability and safety of the oil and gas pipeline network, inspections are implem... Oil and gas pipeline networks are a key link in the coordinated development of oil and gas both upstream and downstream.To improve the reliability and safety of the oil and gas pipeline network, inspections are implemented to minimize the risk of leakage, spill and theft, as well as documenting actual incidents. In recent years, unmanned aerial vehicles have been recognized as a promising option for inspection due to their high efficiency. However, the integrated optimization of unmanned aerial vehicle inspection for oil and gas pipeline networks, including physical feasibility, the performance of mission, cooperation, real-time implementation and three-dimensional(3-D) space, is a strategic problem due to its large-scale,complexity as well as the need for efficiency. In this work, a novel mixed-integer nonlinear programming model is proposed that takes into account the constraints of the mission scenario and the safety performance of unmanned aerial vehicles. To minimize the total length of the inspection path, the model is solved by a two-stage solution method. Finally, a virtual pipeline network and a practical pipeline network are set as two examples to demonstrate the performance of the optimization schemes. Moreover, compared with the traditional genetic algorithm and simulated annealing algorithm, the self-adaptive genetic simulated annealing algorithm proposed in this paper provides strong stability. 展开更多
关键词 PIPELINE network Unmanned AERIAL vehicle INSPECTION MIXED-INTEGER nonlinear PROGRAMMING TWO-STAGE solution
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电位对S22053不锈钢在6%FeCl3溶液中耐腐蚀性能的影响 被引量:5
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作者 孔韦海 艾志斌 +2 位作者 万章 张强 胡盼 《材料保护》 CAS CSCD 北大核心 2019年第7期48-53,共6页
目前研究多通过成膜电位或动电位研究电位对材料钝化膜性能的影响。为给工程技术人员提供理论参考,采用阳极极化、恒电位成膜极化、Mott-Schottky以及电化学阻抗谱测试技术,将成膜电位和动电位相结合组合成3种模式,通过对比不同测试条... 目前研究多通过成膜电位或动电位研究电位对材料钝化膜性能的影响。为给工程技术人员提供理论参考,采用阳极极化、恒电位成膜极化、Mott-Schottky以及电化学阻抗谱测试技术,将成膜电位和动电位相结合组合成3种模式,通过对比不同测试条件下阻抗的变化,研究了电位对S22053在6%(质量分数) FeCl3溶液中的耐腐蚀性能的影响。结果表明:成膜电位在0.3~0.8 V区间,电位越正,载流子浓度越低,钝化膜越稳定,材料在体系中耐腐蚀性越强;0.9 V时钝化膜稳定性降低,材料耐腐蚀性降低;扫描电位在0.3~0.6 V时,钝化膜呈n型半导体特征,载流子以自由电子为主,钝化膜生成占主导,阻抗随电位的升高而增大,材料耐腐性增强;扫描电位在0.6~0.9V时,钝化膜呈p型半导体特征,载流子以空穴为主,钝化膜溶解占主导,阻抗随电位的升高而减小,材料耐腐蚀性降低;成膜后成膜电位下形成的钝化膜比动电位下形成的稳定性好,材料的耐腐蚀性也更好。 展开更多
关键词 成膜电位 电化学阻抗谱 Mott-Schottky曲线 耐腐蚀性能
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Fabrication of TiO_2(B)/anatase heterophase junctions in nanowires via a surface-preferred phase transformation process for enhanced photocatalytic activity 被引量:4
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作者 Yilan wang wan zhang +4 位作者 Zihao wang Yimeng Cao Jiami Feng Zenglin wang Yi Ma 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第9期1500-1510,共11页
Heterojunction fabrication is one of the most effective strategies for enhancing the photocatalytic performance of semiconductor photocatalysts. Here, TiO2(B)/anatase nanowires with interfacial heterostructures were... Heterojunction fabrication is one of the most effective strategies for enhancing the photocatalytic performance of semiconductor photocatalysts. Here, TiO2(B)/anatase nanowires with interfacial heterostructures were prepared through a three-step synthesis method, including hydrothermal treatment, H+ exchange, and annealing. The phase structures of the nanowires in the bulk and on the surface during the annealing process were monitored by XRD and UV-Raman spectroscopy, respectively. SEM and TEM results indicate that the TiO2(B) nanowires partially collapse and transform into anatase during the annealing process and the heterophase junction structure is formed simultaneously. On the basis of the phase structure together with morphology data, a phase-transformation mechanism was proposed. Photocatalytic activity was evaluated by hydrogen production and pollutant-degradation assays. The optimized structure of the photocatalyst contains 24% TiO2(B) in the bulk and 100% anatase on the surface. The charge-carrier behavior during the photocatalytic process was investigated by photocurrent, electrochemical impedance spectroscopy(EIS), and photoluminescence(PL) spectroscopy, which revealed that the heterophase-junction structure in the bulk was responsible for the highly efficient charge separation and transportation, etc.; the anatase on the surface took control of the high surface-reaction activity. 展开更多
关键词 TiO2(B)/anatase Heterophase junction Surface‐preferred Photocatalysis PHASETRANSFORMATION
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COPD患者认知功能障碍及血浆NGAL、ET-1水平变化的研究 被引量:7
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作者 戈艳蕾 刘聪辉 +8 位作者 付爱双 崔紫阳 张婉 李立群 樊蕴辉 张嘉宾 张盼盼 王红阳 胡玲玲 《中国现代医学杂志》 CAS 2018年第17期73-76,共4页
目的探讨慢性阻塞性肺疾病(COPD)患者认知障碍及血浆中性粒细胞明胶酶相关脂质运载蛋白(NGAL)及内皮素-1(ET-1)水平变化的意义。方法选取COPD患者(COPD组)312例,同期匹配健康查体者(对照组)89例,比较认知功能障碍及合并认知功能障碍与... 目的探讨慢性阻塞性肺疾病(COPD)患者认知障碍及血浆中性粒细胞明胶酶相关脂质运载蛋白(NGAL)及内皮素-1(ET-1)水平变化的意义。方法选取COPD患者(COPD组)312例,同期匹配健康查体者(对照组)89例,比较认知功能障碍及合并认知功能障碍与否患者的NGAL、ET-1水平。结果与对照组相比,COPD组视空间执行能力、注意力、延时回忆及Mo CA总分较低(P<0.05)。COPD组血浆NGAL、ET-1水平高于对照组(P<0.05)。对照组有认知功能障碍患者血浆NGAL、ET-1水平高于无认知功能障碍者(P<0.05)。COPD组有认知功能障碍者血浆NGAL、ET-1水平高于无认知功能障碍者(P<0.05)。结论 COPD患者认知功能损害较正常对照人群增加,合并认知障碍人群血浆NGAL及ET-1升高。 展开更多
关键词 慢性阻塞性肺疾病 认知功能障碍 中性粒细胞明胶酶蛋白 内皮素-1
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L320原油输送管道静置段的腐蚀机理 被引量:6
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作者 孔韦海 艾志斌 +4 位作者 胡盼 万章 张强 王萌萌 费勤楠 《腐蚀与防护》 CAS 北大核心 2019年第7期502-506,共5页
选取某腐蚀穿孔L320输油管道静置段作为研究对象,通过现场调研、理化检验和电化学方法等方法,研究了原油输送管道静置段的腐蚀原因。结果表明,原油输送管道静置段的服役环境主要为含H2S、CO2、矿化物的油水混合介质,腐蚀失效主要集中在... 选取某腐蚀穿孔L320输油管道静置段作为研究对象,通过现场调研、理化检验和电化学方法等方法,研究了原油输送管道静置段的腐蚀原因。结果表明,原油输送管道静置段的服役环境主要为含H2S、CO2、矿化物的油水混合介质,腐蚀失效主要集中在管道内壁的5~7点钟部位,腐蚀产物呈疏松状,含有S、O、C、Fe元素,失效的主导因素为含H2S与CO2的原油沉积水引起的局部腐蚀。此外,疏松状的腐蚀产物有加速腐蚀的作用,腐蚀形态也由局部腐蚀转变为均匀腐蚀。 展开更多
关键词 原油 腐蚀机理 沉积水 局部腐蚀
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不锈钢硫酸-硫酸铜晶间腐蚀试验国内外标准对比解析 被引量:8
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作者 张艳 万章 +2 位作者 王晓峰 吴磊 徐鹏程 《理化检验(物理分册)》 CAS 2019年第2期102-107,共6页
不锈钢硫酸-硫酸铜晶间腐蚀试验作为一种广泛应用的晶间腐蚀试验方法,各国对其制定了不同的标准。以GB/T 4334,ASTM A262,ISO 3651-2,RCC-M等标准为例,从试样制备、敏化处理、试验过程和结果评定4个方面对比分析了国内外各标准的差异。... 不锈钢硫酸-硫酸铜晶间腐蚀试验作为一种广泛应用的晶间腐蚀试验方法,各国对其制定了不同的标准。以GB/T 4334,ASTM A262,ISO 3651-2,RCC-M等标准为例,从试样制备、敏化处理、试验过程和结果评定4个方面对比分析了国内外各标准的差异。结果表明:国标和国外标准的规定不尽相同,实际操作过程中可适当相互借鉴;国标对试样制备的表述最为详细,试样表面粗糙度对试验结果的影响并不明显;国标对敏化处理制度的规定最为严格;弯曲参数的选择对试验结果存在一定的影响,过小的弯曲半径容易导致误判。 展开更多
关键词 不锈钢 晶间腐蚀试验 硫酸-硫酸铜 弯曲 标准解析
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NO removal performance of CO in carbonation stage of calcium looping for CO_(2) capture 被引量:2
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作者 wan zhang Yingjie Li +3 位作者 Yuqi Qian Boyu Li Jianli Zhao Zeyan wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第9期30-38,共9页
Calcium looping realizes CO_(2)capture via the cyclic calcination/carbonation of CaO.The combustion of fuel supplies energy for the calciner.It is unavoidable that some unburned char in the calciner flows into the car... Calcium looping realizes CO_(2)capture via the cyclic calcination/carbonation of CaO.The combustion of fuel supplies energy for the calciner.It is unavoidable that some unburned char in the calciner flows into the carbonator,generating CO due to the hypoxic atmosphere in the carbonator.CO can reduce NO in the flue gases from coal-fired power plants.In this work,NO removal performance of CO in the carbonation stage of calcium looping for CO_(2)capture was investigated in a bubbling fluidized bed reactor.The effects of carbonation temperature,CO concentration,CO_(2)capture,type of CaO,number of CO_(2)capture cycles and presence of char on NO removal by CO in carbonation stage of calcium looping were discussed.CaO possesses an efficient catalytic effect on NO removal by CO.High temperature and high CO concentration lead to high NO removal efficiency of CO in the presence of CaO.Taking account of better NO removal and CO_(2)capture,the optimal carbonation temperature is 650℃.The carbonation of CaO reduces the catalytic activity of CaO for NO removal by CO due to the formation of CaCO_(3).Besides,the catalytic performance of CaO on NO removal by CO gradually decreases with the number of CO_(2)capture cycles.This is because the sintering of CaO leads to the fusion of CaO grains and blockage of pores in CaO,hindering the diffusion of NO and CO.The high CaO content and porous structure of calcium-based sorbents are beneficial for NO removal by CO.The presence of char promotes NO removal by CO in the carbonator.CO_(2)/NO removal efficiencies can reach above 90%.The efficient simultaneous NO and CO_(2)removal by CO and CaO in the carbonation step of the calcium looping seems promising. 展开更多
关键词 Sorbents Carbon monoxide CO_(2)capture NO removal Carbonation stage Calcium looping
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S22053不锈钢在6%FeCl_3溶液中的点蚀行为 被引量:3
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作者 万章 孔韦海 张强 《腐蚀与防护》 CAS 北大核心 2019年第1期18-22,共5页
采用动电位电化学阻抗谱技术研究了不同电位条件下S22053不锈钢在6%(质量分数)FeCl_3溶液中的点蚀行为。结果表明,电位为0.3~0.9V(SCE,下同)时,S22053不锈钢处于稳定的钝化状态;电位为1.0V时,钝化膜上诱导点蚀;电位为1.1~1.2V时,蚀坑... 采用动电位电化学阻抗谱技术研究了不同电位条件下S22053不锈钢在6%(质量分数)FeCl_3溶液中的点蚀行为。结果表明,电位为0.3~0.9V(SCE,下同)时,S22053不锈钢处于稳定的钝化状态;电位为1.0V时,钝化膜上诱导点蚀;电位为1.1~1.2V时,蚀坑持续扩展,且以向蚀坑深处扩展为主;电位为1.3~1.4V时,新的点蚀在钝化部位诱导产生。点蚀发生后,电化学阻抗谱主要表征蚀坑处的特征。 展开更多
关键词 S22053不锈钢 点蚀 动电位电化学阻抗谱 FeCl3溶液
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不同钝化工艺对S22053不锈钢腐蚀行为的影响 被引量:2
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作者 张强 孔韦海 +3 位作者 万章 吴志刚 胡盼 刘燕 《材料保护》 CAS CSCD 北大核心 2020年第6期115-120,共6页
针对同一种材料经不同钝化工艺处理后钝化膜的形成、耐蚀性的优劣、钝化后腐蚀行为的比较鲜有报道,为此,通过极化曲线、电化学阻抗谱、临界点蚀温度、再钝化温度测试等方法考察了自然钝化、阳极钝化和酸洗钝化3种钝化工艺对S22053不锈... 针对同一种材料经不同钝化工艺处理后钝化膜的形成、耐蚀性的优劣、钝化后腐蚀行为的比较鲜有报道,为此,通过极化曲线、电化学阻抗谱、临界点蚀温度、再钝化温度测试等方法考察了自然钝化、阳极钝化和酸洗钝化3种钝化工艺对S22053不锈钢耐腐蚀性能的影响,并通过扫描电镜观察了腐蚀前后试样表面的表面形貌。结果表明:阳极钝化和酸洗钝化都可以提高S22053不锈钢的耐腐蚀性能,采用20%(质量分数)硝酸酸洗钝化后不锈钢的耐腐蚀性能最好;不同钝化工艺对S22053不锈钢的点蚀电位影响并不显著,但会显著改变不锈钢的阻抗和临界点蚀温度;点腐蚀发生后腐蚀前沿有明显的沿晶腐蚀倾向,同时伴随有奥氏体晶粒的优先溶解。 展开更多
关键词 钝化 S22053不锈钢 临界点蚀温度 电化学阻抗谱 沿晶腐蚀
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耐蚀合金临界点蚀温度标准试验方法比较 被引量:2
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作者 万章 孔韦海 张强 《腐蚀与防护》 CAS 北大核心 2019年第2期105-109,共5页
对失重法、恒电位法和动电位法三种标准临界点蚀温度(CPT)测定方法进行了对比,分析三种试验方法的特点及适应性,着重研究了不同试验环境和方法对S22053双相不锈钢CPT测定的影响。结果表明:由于试验条件及判定发生点蚀的临界条件有所不同... 对失重法、恒电位法和动电位法三种标准临界点蚀温度(CPT)测定方法进行了对比,分析三种试验方法的特点及适应性,着重研究了不同试验环境和方法对S22053双相不锈钢CPT测定的影响。结果表明:由于试验条件及判定发生点蚀的临界条件有所不同,三种测试方法测得的S22053双相不锈钢的CPT不同,分别为35.6,53.1,55.0℃。失重法采用的试验环境最苛刻,测得的CPT远低于恒电位法和动电位法测得的,且测试时间长,对于单一材料的点蚀形成过程不能准确地描述,但对设备要求低,且操作简单;动电位法和恒电位法对设备要求高,尤其是恒电位法,其升温速率和溶液中的温度梯度对试验结果均存在影响,但二者的测量参数都可较准确地反映材料形成稳态点蚀的临界条件;且恒电位法还具有试样数量少、测试时间短及测得的CPT为一个具体的数值等优点。 展开更多
关键词 临界点蚀温度 失重法 动电位法 恒电位法
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成膜电位对S22053不锈钢在FeCl_3溶液中钝化膜性能的影响 被引量:1
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作者 孔韦海 万章 +2 位作者 艾志斌 张强 胡盼 《机械工程材料》 CAS CSCD 北大核心 2019年第4期15-19,63,共6页
应用阳极极化、恒电位成膜极化、电化学阻抗谱以及Mott-Schottky测试等方法研究了在质量分数6%FeCl_3溶液中S22053不锈钢表面钝化膜的性能。结果表明:S22053不锈钢的成膜电位在0.3~0.9V;当成膜电位在0.3~0.8V时,随成膜电位的增加阻抗... 应用阳极极化、恒电位成膜极化、电化学阻抗谱以及Mott-Schottky测试等方法研究了在质量分数6%FeCl_3溶液中S22053不锈钢表面钝化膜的性能。结果表明:S22053不锈钢的成膜电位在0.3~0.9V;当成膜电位在0.3~0.8V时,随成膜电位的增加阻抗最大模值增大,钝化膜稳定性增强,当成膜电位在0.8~0.9V时则相反;在不同成膜电位极化30min成膜后,钝化膜在扫描电位0~0.6V范围内均呈n型半导体特征,在0.6~0.9V范围内呈p型半导体特征;由电化学阻抗谱测试得到的钝化膜厚度和由Mott-Schottky曲线得到的空间电荷层厚度随成膜电位的变化趋势一致,二者均在成膜电位0.8V时出现峰值。 展开更多
关键词 成膜电位 S22053不锈钢 电化学阻抗谱 Mott-Schottky曲线 钝化膜
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The chloroplast genome comparative characteristic of artificial breeding tree,a case about Broussonetia kazinoki×Broussonetia papyrifera 被引量:1
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作者 wan zhang GUIYAN YANG +3 位作者 YUNLIN ZHAO ZHENGGANG XU HUANG HUIMIN JIAKANG ZHOU 《BIOCELL》 SCIE 2022年第3期803-819,共17页
Broussonetia kazinoki×Broussonetia papyrifera(ZJGS)is a hybrid species in Moraceae family,which has a very complicated hybrid origin.The excellent characteristics of fast growth,strong soil and water conservation... Broussonetia kazinoki×Broussonetia papyrifera(ZJGS)is a hybrid species in Moraceae family,which has a very complicated hybrid origin.The excellent characteristics of fast growth,strong soil and water conservation ability,high leaf protein content and stem fiber content in ZJGS make it both ecological benefits in the mining area and economically valuable.This study aims to further understand ZJGS and other Moraceae taxa through the ZJGS chloroplast(cp)genome structure and the comparison with 12 closely related Moraceae species.Among the 13 Moraceae species,the cp genome length of seven Broussonetia species(ranges from 160,239 bp to 162,594 bp)is larger than that of six Morus species(ranges from 158,459 bp to 159,265 bp).Among the 77 shared protein-coding genes(PCGs)in Moraceae species,the obvious positive selection of Ka/Ks ratios acted on petD and rpl16 genes of B.kazinoki and B.papyrifera,respectively.Phylogenetic analysis based on shared PCGs from 28 species shows that ZJGS is closely related to maternal B.kazinoki.These findings provide data support for the origin of ZJGS hybridization and provide genomic resources for future ZJGS resource development and molecular breeding. 展开更多
关键词 Broussonetia kazinoki Broussonetia papyrifera MORACEAE Phylogenetic relationship Maternal inheritance
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