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Analysis of the Application and Effect of Homemade Medical Scrotal Support Shorts
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作者 Jianbin Cheng xiaohui liu Lin Lin 《Journal of Clinical and Nursing Research》 2024年第2期244-248,共5页
Objective:To design and manufacture medical scrotal support shorts for patients with enlarged scrotum and observe its application and effect.Methods:40 patients with enlarged scrotum admitted to the basic surgery depa... Objective:To design and manufacture medical scrotal support shorts for patients with enlarged scrotum and observe its application and effect.Methods:40 patients with enlarged scrotum admitted to the basic surgery department from February 2021 to March 2023 were selected and divided into a test group and a control group according to their time of admission,with the test group using scrotal support shorts and the control group using ordinary shorts without scrotal support pockets or diapers.Results:The complication rate of skin injury in the scrotum and the surrounding inguinal area of the patients in the test group was significantly lower than that of the control group(P<0.01).The medical cost covered by patients in the test group was significantly lower than that of the control group(P<0.01)and the hospitalization satisfaction of the patients in the test group was significantly higher than that of the control group(P<0.01).The difference in the therapeutic effect of the test groups was statistically significant when compared with the control group(P<0.05).Conclusion:Homemade medical scrotal support shorts reduced the local enlargement of the scrotum and bleeding,but also protected the scrotum and the surrounding skin to prevent secondary injuries.The process of patient care was simple and promoted their recovery.The length of hospitalization was also decreased,the burden of health care costs was reduced,and the overall comfort and satisfaction of the patient was improved. 展开更多
关键词 Enlarged scrotum Medical scrotal support shorts Nursing care
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Co@CoO催化剂表面类氢负物种NH_(2)^(δ-)驱动下的还原胺化反应
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作者 郭万君 王志强 +5 位作者 相爽 景亚轩 刘晓晖 郭勇 龚学庆 王艳芹 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第4期181-190,共10页
胺类化合物作为一类重要的精细化学品,广泛应用于合成染料、表面活性剂、聚合物、药品和农用化学品.催化还原胺化是合成胺类化合物的重要手段.在还原胺化反应中,水是唯一的副产物,且反应条件温和,符合绿色化学原则,因此受到了广泛关注.... 胺类化合物作为一类重要的精细化学品,广泛应用于合成染料、表面活性剂、聚合物、药品和农用化学品.催化还原胺化是合成胺类化合物的重要手段.在还原胺化反应中,水是唯一的副产物,且反应条件温和,符合绿色化学原则,因此受到了广泛关注.在过去的几十年里,生物质衍生的羰基化合物(糠醛、环戊酮、5-羟甲基糠醛等)的催化还原胺化得到了特别关注,为利用可再生资源可持续地生产胺类提供了可能性.通常,金属(Ru,Ir,Pt,Rh,Co,Ni等)被认为是还原胺化的活性中心,相关研究快速发展,但大部分研究都围绕着金属负载型催化剂展开,对于以金属氧化物为活性中心鲜有研究.另外,还原胺化过程研究表明,席夫碱在反应开始阶段迅速生成,然后通过氨解产生相应的伯胺;但席夫碱氨解为伯胺的过程速率较慢,是该反应的决速步骤,因此设计高效催化剂加快席夫碱的氨解是还原胺化过程中的重要科学问题.受孤立的路易斯酸碱对可以催化氢气异裂过程的启发,本文利用具有核壳结构的Co@Co O为催化剂,发现表面具有氧空位的CoO具有独特的解离NH_(3)生成类氢负物种(NH_(2)^(δ-))的能力,该NH_(2)^(δ-)物种能够加速席夫碱的氨解,从而使得该催化剂展现出较好的还原胺化性能,且具有较好的稳定性,在环戊酮胺化为环戊胺过程中使用10次没有失活.通过密度泛函理论(DFT)计算和D_(2)同位素示踪实验发现了类氢负物种NH_(2)^(δ-),且验证了H^(δ-)和NH_(2)^(δ-)物种在Co O表面可稳定地共吸附,席夫碱在催化剂表面吸附较弱,使得希夫碱中间体可以在解离NH_(2)^(δ-)和H^(δ-)后的CoO表面自由移动,从而与表面解离的H^(-)和NH_(2)^(δ)–发生分子碰撞,生成伯胺,最后脱附完成催化循环.本文实现了金属氧化物催化还原胺化反应.更重要的是,在加氢/氢解反应中,孤立的路易斯酸碱对上异裂产生的H^(δ-)物种虽然具有较好的活性,但是没有H^(δ-)物种参与反应直接证据的相关报道,本研究发现的类氢负物种NH_(2)^(δ-)参与胺化反应的证据间接表明了H^(δ-)物种参与加氢/氢解反应的可能性. 展开更多
关键词 还原胺化 类氢负物种NH_(2)^(δ-) Co@CoO 席夫碱
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Fe的原位掺杂对Pt/Silicalite-1催化丙烷脱氢反应性能的提升作用
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作者 沈姗姗 刘晓晖 +1 位作者 郭勇 王艳芹 《物理化学学报》 SCIE CAS CSCD 北大核心 2023年第7期79-88,共10页
利用一步水热法制备了原位掺杂Fe的Silicalite-1分子筛载体,浸渍得到相应的Pt基催化剂,用于丙烷的直接脱氢反应。作为对比,也制备了Pt/Silicalite-1和共浸渍的Pt1Fe2/Silicalite-1催化剂。研究发现较之Pt/Silicalite-1催化剂,原位掺入Fe... 利用一步水热法制备了原位掺杂Fe的Silicalite-1分子筛载体,浸渍得到相应的Pt基催化剂,用于丙烷的直接脱氢反应。作为对比,也制备了Pt/Silicalite-1和共浸渍的Pt1Fe2/Silicalite-1催化剂。研究发现较之Pt/Silicalite-1催化剂,原位掺入Fe的Pt/Fe-Silicalite-1催化剂反应性能有了很大程度地提高,而共浸渍制备的Pt1Fe2/Silicalite-1催化剂反应性能有所降低。在Pt/Fe-Silicalite-1催化剂上,尽管丙烷的初始转化率略有降低,但丙烯的选择性和催化稳定性大幅提高。反应8h后丙烷转化率稳定在43.7%、丙烯选择性达到98.0%;且在80h内基本保持不变。深入表征发现Fe的原位掺入使得Pt物种配位饱和度提高,避免了丙烷的深度脱氢使得丙烯选择性提高、结焦速率降低;且通过Fe-Pt之间电子转移,使得Pt上的电子云密度增强,增强了丙烯的脱附能力,进一步降低了结焦速率。另外载体中的Fe位点可以锚定Pt,使得Pt物种不易聚集,从而进一步提高了Pt/Fe-Silicalite-1的稳定性,使得该催化剂在反应80 h后仍保持高转化率和选择性。 展开更多
关键词 丙烷脱氢 SILICALITE-1 Pt基催化剂 Fe原位掺杂
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Co@CoO:An efficient catalyst for the depolymerization and upgrading of lignocellulose to alkylcyclohexanols with cellulose intact
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作者 Shuang Xiang Lin Dong +5 位作者 Zhiqiang Wang Xue Han Yong Guo xiaohui liu Xue-Qing Gong Yanqin Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期191-199,I0006,共10页
The depolymerization and upgrading of lignin from raw biomass,while keeping cellulose intact is important in biorefinery and various metal-based catalysts have been used in reductive catalytic fractionation,a key meth... The depolymerization and upgrading of lignin from raw biomass,while keeping cellulose intact is important in biorefinery and various metal-based catalysts have been used in reductive catalytic fractionation,a key method in"lignin-first"strategy,Recently,we found that a core-shell structured Co@CoO catalyst with CoO shell as the real active site had excellent performance in the hydrogenolysis of 5-hydromethylfurfural to 2,5-dimethylfuran due to its unique ability to dissociate H_(2)and yield active H^(δ-)species(Xiang et al.,2022).In this work,we report a one-pot depolymerization and upgrading of lignocellulose to alkylcyclohexanols,a flavour precursor,with intact cellulose over this unique core-shell structured catalyst,Co@CoO.Lignin model compounds(β-O-4,4-O-5,α-O-4)were first used to clarify the activity of Co@CoO catalyst.Then,the one-pot conversion of various organosolv lignin(birch,pine and poplar)to alkylcyclohexanols was realized with the mass yield of alkylcyclohexanols up to25.8 wt%from birch lignin under the reaction condition of 210℃,1 MPa H_(2),16 h.Finally,the corresponding woody sawdusts were used as feedstocks and found that the Co@CoO catalyst indeed preferentially depolymerized and upgraded the lignin part and obtained the same alkylcyclohexanols products with the retention of cellulose-rich pulp.The collected alkylcyclohexanols were further esterified to obtain valueadded esters,which can be used as flavors.This work will inspire the design of new efficient metal oxide catalysts in lignin fractionation and depolymerization to high-value-added chemicals with intact cellulose. 展开更多
关键词 LIGNOCELLULOSE LIGNIN DEPOLYMERIZATION Co@CoO Alkylcyclohexanols
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木质素在不同Ru/Nb基催化剂上解聚和脱氧加氢制芳烃化合物(英文) 被引量:5
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作者 马迪 陆圣璐 +2 位作者 刘晓晖 郭勇 王艳芹 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第4期609-617,M0006,共10页
木质素高效转化为芳烃是木质素利用的一个非常重要的过程,一般通过解聚和脱氧加氢反应来实现.我们曾发现NbOx物种在木质素及其模型化合物的C–O键活化和断裂的过程中发挥了至关重要的作用.本文分别选择两种商业的铌基材料(HY-340和NbPO-... 木质素高效转化为芳烃是木质素利用的一个非常重要的过程,一般通过解聚和脱氧加氢反应来实现.我们曾发现NbOx物种在木质素及其模型化合物的C–O键活化和断裂的过程中发挥了至关重要的作用.本文分别选择两种商业的铌基材料(HY-340和NbPO-CBMM)和实验室自制的具有层状结构的氧化铌材料(Nb_2O_5-Layer)为载体,制备了负载型Ru催化剂,将其用于木质素及其模型化合物的催化转化.同时,为了尽量避免Ru与铌基载体相互作用的影响,制备了较为均匀的Ru纳米胶粒并吸附于铌基载体上,得到Ru@铌基催化剂,并用于木质素模型化合物—对甲酚的催化转化反应中.研究表明,木质素在所有的Ru/铌基催化剂上都可以得到比较高的C7–C9碳氢化合物的收率.其中,在Ru/Nb_2O_5-Layer催化剂上C_7–C_9碳氢化合物的摩尔收率为99.1%,选择性为88.0%.采用X射线衍射、N_2吸附-脱附、热重分析、吡啶吸附红外光谱(Py-FTIR)、X射线光电子能谱(XPS)以及CO化学吸附等技术表征了Ru/铌基催化剂的性能与铌基材料的性质、金属Ru颗粒大小及其表面电子状态之间的关系.Py-FTIR结果表明, Nb_2O_5-Layer材料上几乎没有Br?nsted酸,但含有最多的Lewis酸,而NbPO-CBMM上的Lewis酸量最低.结合催化性能数据发现,单体产物收率与铌基载体的Lewis量成正相关关系,其中以Ru/Nb_2O_5-Layer催化剂上最高.CO化学吸附和XPS结果表明,不同的铌基载体负载的金属Ru的分散度和电子状态都有差异.在Ru/Nb_2O_5-Layer上Ru的分散度最好,颗粒尺寸最小,木质素转化得到的芳烃选择性最好;在Ru/HY-340和Ru/NbPO-CBMM上,虽然Ru的分散度相近,但其表面电子状态不同, Ru/HY-340上的金属态Ru带有更多的正电荷δ+,其得到芳烃的选择性高于Ru/Nb PO-CBMM.由此可见, Ru的颗粒尺寸和表面电子状态会影响芳烃选择性.对甲酚催化转化反应结果表明, Ru颗粒大小相同时,铌基载体性质会影响对甲酚转化率;而同一铌基载体上, Ru颗粒大小则影响芳烃选择性,较小的Ru颗粒有利于芳烃的生成. 展开更多
关键词 木质素 芳烃化合物 铌基载体 路易斯酸
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低成本合成纳米堆积的SAPO-34分子筛及其在糠醇催化醇解反应中的应用 被引量:3
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作者 郭倩倩 杨帆 +3 位作者 刘晓晖 孙孟清 郭勇 王艳芹 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第11期1772-1781,共10页
SAPO-34分子筛因其规则的孔结构、独特的择形性和适宜的酸性,在石油化工领域有着重要的应用.本文不添加四乙基氢氧化铵(TEAOH)之外的模板剂,仅改变原料的加入顺序,通过水热合成法制备了两种不同形貌的SAPO-34分子筛(纳米堆积SAPO-34和... SAPO-34分子筛因其规则的孔结构、独特的择形性和适宜的酸性,在石油化工领域有着重要的应用.本文不添加四乙基氢氧化铵(TEAOH)之外的模板剂,仅改变原料的加入顺序,通过水热合成法制备了两种不同形貌的SAPO-34分子筛(纳米堆积SAPO-34和立方体SAPO-34).结果表明,前驱体的存在形式和成核速率是导致形貌不同的主要原因.拟薄水铝石和正硅酸乙酯在碱性条件下水解,铝和硅的前驱体分别以Al(OH)4-和SiO2(OH)-的形式存在,二者相互结合生成分子筛生长的基本单元:具有Si–O–Al键的硅铝酸化合物,它们倾向于形成更多的如低聚物、非晶态颗粒或纳米晶等的二级单元,这些二级单元均有利于晶核的快速生成,并在范德华力的作用下进行自组装,形成聚集体堆积的球形纳米晶,纳米晶继续长大,最终生成了结晶度较高的纳米聚集体SAPO-34.而在酸性体系中,铝和硅的前驱体分别以Al3+和(OH)3Si(OH2)+的形式存在,TEAOH加入后,铝会在硅表面沉积,从而显著减慢Si–O–Si键的断裂,使得晶核生成的速度减慢,最终通过一层一层生长的机制进行晶体生长而形成较大的立方体SAPO-34.为了进一步探讨形貌结构对SAPO-34分子筛酸催化性能的影响,我们选择分子尺寸略大于传统SAPO-34孔道尺寸(约0.38 nm)的生物质基糠醇(FAL,约0.53 nm)为模型反应物,分别研究了纳米堆积SAPO-34和立方体SAPO-34分子筛在糠醇醇解制备乙酰丙酸乙酯(EL)反应中的催化性能.与传统的立方体SAPO-34相比,纳米堆积SAPO-34分子筛由于纳米晶的堆积具有较大的外比表面积和堆积介孔孔容,从而具有更多的外表面酸性,因此在糠醇醇解反应中表现出更高的EL收率(74.1%),而立方SAPO-34仅有19.9%的EL收率.此外,纳米堆积SAPO-34分子筛也因其具有较大的外比表面和堆积介孔孔容,利于反应过程中乙氧基甲基呋喃中间体、产物及副产物的传质,减少了碳的沉积,从而改善了其稳定性. 展开更多
关键词 纳米堆积SAPO-34 外比表面 低成本 催化醇解 糠醇
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氧化铌高效催化生物质衍生物的羟醛缩合反应制备燃料前驱体(英文) 被引量:3
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作者 景亚轩 辛宇 +2 位作者 郭勇 刘晓晖 王艳芹 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第8期1168-1177,共10页
生物质是自然界唯一可再生的有机碳来源,其催化转化制备燃料和精细化学品受到广泛关注.一般从生物质衍生的小分子出发制备航空煤油和柴油等高碳数燃料包括两步:首先通过碳链增长反应如羟醛缩合和烷基化等制备目标链结构的燃料前驱体,然... 生物质是自然界唯一可再生的有机碳来源,其催化转化制备燃料和精细化学品受到广泛关注.一般从生物质衍生的小分子出发制备航空煤油和柴油等高碳数燃料包括两步:首先通过碳链增长反应如羟醛缩合和烷基化等制备目标链结构的燃料前驱体,然后对所得燃料前驱体进行完全脱氧加氢得到燃料组分.在目前报道的碳链增长反应中,羟醛缩合反应应用最多,因为生物质衍生的羰基化合物众多,而且丙酮、糠醛及环己酮等羰基化合物已经实现了工业化生产.羟醛缩合反应的催化剂以碱性材料为主,但是碱性催化剂具有不抗二氧化碳、不抗水等缺点,因此开发高活性的固体酸催化剂至关重要.本文选择糠醛和4-庚酮的羟醛缩合反应作为模型反应,发现氧化铌材料对该反应具有优异的催化活性,活性明显高于常见的氧化钙、氧化镁、镁铝水滑石等固体碱和氧化铝、氧化锆等固体酸.并采用N2吸附-脱附、二氧化碳程序升温脱附(CO-TPD)、吡啶吸附红外光谱(Py-FTIR)、程序升温氨脱附(NH3-TPD)和丙酮的原位吸附傅立叶变换红外光谱等表征手段研究了氧化铝,氧化锆和氧化铌催化性能差异的原因.结果表明,这三种催化剂的比表面积和酸性质与反应活性没有明显关联.为了解释反应活性的差异,我们采用丙酮原位吸附红外光谱探究了这三种催化剂对羰基的活化.发现相比于氧化铝和氧化锆催化剂,氧化铌对丙酮的C=O双键有更强的活化能力,使C=O双键结构更容易转化为烯醇式结构,进而促进羟醛缩合反应的进行.基于此,我们提出了氧化铌催化羟醛缩合的反应机理.另外,底物拓展实验发现,在其他生物质相关的羟醛缩合反应体系中,氧化铌催化依旧可以得到可观的收率.循环套用实验表明,由于积碳导致催化剂失活,通过简单的煅烧即可恢复活性.我们之前的研究发现负载金属的铌基催化剂具有很好的断裂呋喃环上碳氧键的能力,是很好的脱氧加氢催化剂.基于以上研究和我们之前的结论,我们设计并制备了多功能的Pd/Nb2O5催化剂,对该催化剂进行了结构表征,并对羟醛缩合和脱氧加氢过程进行了设计整合,一锅实现了羟醛缩合和后续的脱氧加氢. 展开更多
关键词 羟醛缩合 氧化铌 C=O活化 燃料前驱体 生物燃料 一锅过程
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大数据背景下智慧交通治理模式研究——以中国东莞为例
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作者 刘小慧 李海青 《工程设计与施工》 2020年第12期4-6,共3页
随着科学技术的不断发展和大数据技术的持续进步,智慧交通治理模式开始在当前各大城市进行推广,其应用有效提升了城市交通监管质量,减少了城市堵塞问题,提升了人们的交通体验。论文主要针对大数据背景下智慧交通治理模式在中国东莞的应... 随着科学技术的不断发展和大数据技术的持续进步,智慧交通治理模式开始在当前各大城市进行推广,其应用有效提升了城市交通监管质量,减少了城市堵塞问题,提升了人们的交通体验。论文主要针对大数据背景下智慧交通治理模式在中国东莞的应用进行探究,指出智慧交通治理模式的构建形式以及应用价值,希望能为中国交通行业的持续稳定发展提供一定的参考。 展开更多
关键词 大数据 智慧交通 治理模式
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泵供量和纺丝液浓度对Y形Lyocell纤维截面形状与性能的影响
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作者 沈洋 刘晓慧 +3 位作者 杨革生 张慧慧 于敏敏 邵惠丽 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2020年第10期135-140,共6页
采用Y形截面喷丝孔,通过干喷湿纺制备异形Lyocell纤维,通过扫描电子显微镜、光学显微镜和纤维强伸度仪分别研究了泵供量和纺丝液浓度对纤维截面形状、异形度及力学性能的影响。研究结果表明,尽管采用的喷丝孔截面为Y形,但由于孔口胀大效... 采用Y形截面喷丝孔,通过干喷湿纺制备异形Lyocell纤维,通过扫描电子显微镜、光学显微镜和纤维强伸度仪分别研究了泵供量和纺丝液浓度对纤维截面形状、异形度及力学性能的影响。研究结果表明,尽管采用的喷丝孔截面为Y形,但由于孔口胀大效应,所得Lyocell纤维截面类似三角形。随着泵供量增加,纤维的异形度略有减小,力学性能则先上升后趋于平稳,当泵供量为16 g/min时,可制备出具有较高异形度且断裂强度最高的类三角形Lyocell纤维。随着纺丝液浓度的增大,纤维截面形状更加趋于喷丝孔形状,异形度逐渐提高,同时纤维力学性能也逐渐提高,其中纺丝液浓度为13%时制得的Y形Lyocell纤维的截面形状与力学性能最佳。 展开更多
关键词 LYOCELL纤维 异形纤维 截面形状 力学性能 异形度
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High-yield production of 2,5-dimethylfuran from 5-hydroxymethylfurfural over carbon supported Ni–Co bimetallic catalyst 被引量:7
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作者 Panpan Yang Qineng Xia +1 位作者 xiaohui liu Yanqin Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第6期1015-1020,共6页
The catalytic conversion of 5-hydroxymethylfurfural(HMF) to 2,5-dimethylfuran(DMF) has attracted extensive research interests because DMF can be used as potential and competitive renewable transportation fuel or addit... The catalytic conversion of 5-hydroxymethylfurfural(HMF) to 2,5-dimethylfuran(DMF) has attracted extensive research interests because DMF can be used as potential and competitive renewable transportation fuel or additives. Here we report a non-noble bimetallic catalyst with improved activity for hydrogenation and hydrogenolysis by introducing active carbon as support into a nickel–cobalt catalyst. The characterizations of the catalyst indicate that the Ni and Co species are uniformly dispersed on the active carbon through the wetness impregnation method. The influences of reaction temperature and hydrogen pressure are systematically investigated and an excellent yield(up to 95%) of DMF can be obtained at relatively mild conditions, 130 °C and 1 MPa H_2, over the carbon supported Ni–Co bimetallic catalyst. The high catalytic activity originates from the synergistic effect between Ni and CoO xspecies, the high BET surface area of the catalyst, and the uniform dispersion of Ni and Co species on the active carbon. The catalyst could be reused for 5 times without loss of activity in a batch reactor. Futhermore, the conversion of HMF to DMF on a fixed-bed reactor was also investigated and the 2%Ni–20%Co/C catalyst exhibited an excellent yield to DMF(>90%) for 71 h time on stream, indicating the high activity and stability of the catalyst. 展开更多
关键词 BIOMASS Ni–Co/C HYDROGENOLYSIS 5-HYDROXYMETHYLFURFURAL 2.5-dimethylfuran
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An Overview of Recommendation Techniques and Their Applications in Healthcare 被引量:4
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作者 Wenbin Yue Zidong Wang +1 位作者 Jieyu Zhang xiaohui liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第4期701-717,共17页
With the increasing amount of information on the internet,recommendation system(RS)has been utilized in a variety of fields as an efficient tool to overcome information overload.In recent years,the application of RS f... With the increasing amount of information on the internet,recommendation system(RS)has been utilized in a variety of fields as an efficient tool to overcome information overload.In recent years,the application of RS for health has become a growing research topic due to its tremendous advantages in providing appropriate recommendations and helping people make the right decisions relating to their health.This paper aims at presenting a comprehensive review of typical recommendation techniques and their applications in the field of healthcare.More concretely,an overview is provided on three famous recommendation techniques,namely,content-based,collaborative filtering(CF)-based,and hybrid methods.Next,we provide a snapshot of five application scenarios about health RS,which are dietary recommendation,lifestyle recommendation,training recommendation,decision-making for patients and physicians,and disease-related prediction.Finally,some key challenges are given with clear justifications to this new and booming field. 展开更多
关键词 Collaborative filtering(CF) content-based recommendation healthcare recommendation system(RS)
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Set-Membership Filtering Subject to Impulsive Measurement Outliers:A Recursive Algorithm 被引量:3
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作者 Lei Zou Zidong Wang +1 位作者 Hang Geng xiaohui liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第2期377-388,共12页
This paper is concerned with the set-membership filtering problem for a class of linear time-varying systems with norm-bounded noises and impulsive measurement outliers.A new representation is proposed to model the me... This paper is concerned with the set-membership filtering problem for a class of linear time-varying systems with norm-bounded noises and impulsive measurement outliers.A new representation is proposed to model the measurement outlier by an impulsive signal whose minimum interval length(i.e.,the minimum duration between two adjacent impulsive signals)and minimum norm(i.e.,the minimum of the norms of all impulsive signals)are larger than certain thresholds that are adjustable according to engineering practice.In order to guarantee satisfactory filtering performance,a so-called parameter-dependent set-membership filter is put forward that is capable of generating a time-varying ellipsoidal region containing the true system state.First,a novel outlier detection strategy is developed,based on a dedicatedly constructed input-output model,to examine whether the received measurement is corrupted by an outlier.Then,through the outcome of the outlier detection,the gain matrix of the desired filter and the corresponding ellipsoidal region are calculated by solving two recursive difference equations.Furthermore,the ultimate boundedness issue on the time-varying ellipsoidal region is thoroughly investigated.Finally,a simulation example is provided to demonstrate the effectiveness of our proposed parameter-dependent set-membership filtering strategy. 展开更多
关键词 Boundedness analysis impulsive measurement outliers parameter-dependent filter set-membership filtering time-varying systems
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Construction of Oryza sativa genome contigs by fingerprint strategy 被引量:1
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作者 TAO QUANZHOU YUEMIN QIAN +7 位作者 HAIYING ZHAO SHULIANG YU LONGFANG QIU BOQIAN WU JIA ZHU DI YU xiaohui liu GUOFAN HONG(National Center for Gene Research, Chinese Academy of Sciences, Shanghai 200233, China.)(Shanghai Institute of Biochemistry, Chinese Acad 《Cell Research》 SCIE CAS CSCD 1995年第2期263-271,共9页
We described the construction of BAC contigs of the genome of a indica variety of Oryza sativa, Guang Lu Ai 4.An entire representative (sixfold coverage of rice chromosomes) and genetically stable BAC library of rice ... We described the construction of BAC contigs of the genome of a indica variety of Oryza sativa, Guang Lu Ai 4.An entire representative (sixfold coverage of rice chromosomes) and genetically stable BAC library of rice genome constructed in this lab has been systematically analysed by restriction enzyme fragmentation and polyacrylamide gel electrophoresis. And all the images thus obtained were subject to image-processing, which consisted of preliminary location of bands, cooperative tracking of lanesby correlation of adjacent bands, a precise densitometric pass, alignment at the marker bands with the standard,optional interactive editing, and normalization of the accepted bands. The contigs were generated based on the Computer Software specially designed for genome map ping. The number of contigs with 600 kb in length on average was 464; of contigs with 1000 kb in length on average was 107; of contigs with 1500 kb in length on average was 23. Therefore, all the contigs we have obtained amounted up to 420 megabases in length. Considering the size of rice genome (430 megabased), the contigs generated in this lab have covered nearly 98% of the rice genome. We are now in the process of mapping the contigs to chromosomes. 展开更多
关键词 水稻 基因组 Contigs图 指纹技术 遗传连锁图 作图
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The Temporal Relation between Cardiomyopathy and LBBB and Response to Cardiac Resynchronization Therapy:Case Series and Literature Review 被引量:1
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作者 Sanshuai Chang Yi He +8 位作者 Hui Wang Fei Guo Qiang Lv Junping Kang Rong Bai xiaohui liu Xin Du Changsheng Ma Jianzeng Dong 《Cardiovascular Innovations and Applications》 2020年第1期163-172,共10页
Background:Left bundle branch block(LBBB)-induced cardiomyopathy has been proposed,but the association between LBBB and cardiac resynchronization therapy(CRT)response remains unclear and practical criteria for selecti... Background:Left bundle branch block(LBBB)-induced cardiomyopathy has been proposed,but the association between LBBB and cardiac resynchronization therapy(CRT)response remains unclear and practical criteria for selecting CRT candidates are needed.Methods:One hundred and seventeen consecutive heart failure patients were reviewed,24 of whom received CRT.Only two patients had a clear temporal relation between cardiomyopathy and LBBB.Results:Compared with the patient with“cardiomyopathy-induced LBBB,”the patient with“LBBB-induced cardiomyopathy”had higher left ventricular(LV)wall thickness,higher LV wall thickening rate,higher peak circumferential strain,and longer peak circumferential strain delay.The LV deformation patterns in the two patients were obviously distinct on cardiovascular magnetic resonance tissue tracking.During follow-up,the patient with LBBB-induced cardiomyopathy had a good response to CRT(LV ejection fraction 23 before CRT vs.30%at 6 months vs.29 at 12 months vs.32%at 18 months;LV end-diastolic diameter 77 mm before CRT vs.66 mm at 6 months vs.62 mm at 12 months vs.63 mm at 18 months),and the other patient had no response to CRT(LV ejection fraction 29 before CRT vs.29%at 6 months vs.26 at 12 months vs.22%at 24 months;LV end-diastolic diameter 85 mm before CRT vs.88 mm at 6 months vs.85 mm at 12 months vs.84 mm at 24 months).Conclusion:The temporal relation between cardiomyopathy and LBBB could be a determinant for CRT response.Cardiovascular magnetic resonance tissue tracking may be a useful tool to identify the chronological order and a principal consideration for selecting candidates for CRT.Larger prospective clinical trials are needed to study the prevalence of,time course of,and risk factors for LBBB-induced cardiomyopathy. 展开更多
关键词 LEFT BUNDLE branch block CARDIOMYOPATHY heart failure CARDIOVASCULAR magnetic resonance cardiac RESYNCHRONIZATION therapy
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Effects of Ovarian Preservation Time on in vitro Maturation and in vitro Fertilization of Oocytes from Slaughtered Sheep 被引量:1
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作者 Hongyan LANG xiaohui liu +4 位作者 Pengju ZHANG Weixia WANG Haiyan liu Chengcheng TAN Xintao LI 《Agricultural Biotechnology》 CAS 2018年第3期104-105,109,共3页
[Objectives] The aim was to study the effects of ovarian preservation time on in vitro fertilization of oocytes from slaughtered sheep. [Methods] The collected ovaries were randomly and evenly divided into four groups... [Objectives] The aim was to study the effects of ovarian preservation time on in vitro fertilization of oocytes from slaughtered sheep. [Methods] The collected ovaries were randomly and evenly divided into four groups. They were preserved in physiological saline containing penicillin( 100 IU/ml) and streptomycin( 100 μg/ml) at 15-20 ℃ for 0( Control),6,12 and 18 h,respectively. Then,the oocytes were subjected to in vitro fertilization. [Results]The maturation rates,cleavage rates and blastocyst rates of the oocytes preserved for 6 and 12 h showed no significant differences compared with those of the oocytes preserved for0 h( 72. 03%,70. 87% vs. 73. 68%; 74. 12%,72. 60% vs. 74. 49%; 22. 22%,20. 75% vs. 23. 29%)( P > 0. 05). There were also no significant differences in maturation rate,cleavage rate or blastocyst rate between the oocytes preserved for 18 and 0 h( P > 0. 05). [Conclusions] Within a certain rage( 0-18 h),storage time of ovary at 15-20 ℃ does not affect the continued development of oocytes from slaughtered sheep. 展开更多
关键词 卵母细胞 存储时间 成熟率 卵巢 绵羊 授精 保藏 保存
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Self-assembled interlayer aiming at the stability of NiOx based perovskite solar cells
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作者 Tonghui Guo Zhi Fang +8 位作者 Zequn Zhang Zhiqiang Deng Rui Zhao Jing Zhang Minghui Shang xiaohui liu Ziyang Hu Yuejin Zhu Liyuan Han 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第6期211-220,I0006,共11页
Inorganic NiO_(x) based inverted structure perovskite solar cells (PSCs) is reported to be more stable than that with the organic hole transport materials.In this work,NiO_(x)/MAPbI_(3) interface chemical reaction ind... Inorganic NiO_(x) based inverted structure perovskite solar cells (PSCs) is reported to be more stable than that with the organic hole transport materials.In this work,NiO_(x)/MAPbI_(3) interface chemical reaction induced instability of perovskite is unveiled:Ni^(3+) and I^(-) exhibit redox reactions and deprotonation of MA^(+) happens,which result in interface defects and perovskite lattice deformation.Thus the defective interface accelerates the degradation of perovskite by defect pathways from the bottom interface to the perovskite surface contacting H_(2)O/O_(2).Self-assembled interlayer of NH_(2)^(-)end silane on NiO_(x)separates the reactive NiO_(x)and MAPbI_(3),tunes the interface energy states by–NH_(2) end group.As a result,the PSC based on the silane treated NiO_(x)achieves enhanced PCE of 20.1%with decent stability under environmental and extreme conditions (high temperature,high humidity,light infiltration).Our work highlights the interface chemical problem induced PSC instability and a simple interface modification to achieve the stable PSCs. 展开更多
关键词 Perovskite solar cells Interface chemical problem NiOx hole transport material Self assemble Stability
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The Importance of Flapping Kinematic Parameters in the Facilitation of the Different Flight Modes of Dragonflies
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作者 xiaohui liu Csaba Hefler +1 位作者 Wei Shyy Huihe Qiu 《Journal of Bionic Engineering》 SCIE EI CSCD 2021年第2期419-427,共9页
To better understand dragonflies’remarkable flapping wing aerodynamic performance,we measured the kinematic parameters of the wings in two different flight modes(Normal Flight Mode(NFM)and Escape Flight Mode(EFM)).Wh... To better understand dragonflies’remarkable flapping wing aerodynamic performance,we measured the kinematic parameters of the wings in two different flight modes(Normal Flight Mode(NFM)and Escape Flight Mode(EFM)).When the specimens switched from normal to escape mode the flapping frequency was invariant,but the stroke plane of the wings was more horizontally inclined.The flapping of both wings was adjusted to be more ventral with a change of the pitching angle that resulted in a larger angle of attack during downstroke and smaller during upstroke to affect the flow directions and the added mass effect.Noticeably,the phasing between the fore and hind pair of wings varies between two flight modes,which affects the wing-wing interaction as well as body oscillations.It is found that the momentum stream in the wake of EFM is qualitatively different from that in NFM.The change of the stroke plane angle and the varied pitching angle of the wings diverts the momentum downwards,while the smaller flapping amplitude and less phase difference between the wings compresses the momentum stream.It seems that in order to achieve greater flight maneuverability a flight vehicle needs to actively control positional angle as well as the pitching angle of the flapping wings. 展开更多
关键词 wing kinematics flight mode dragonfly flight AERODYNAMICS
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Strengthening the Role of Ocular Pathology in Clinical Thinking Training Targeting for House Staff
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作者 Yungang Ding Wenxin Zhang +3 位作者 xiaohui liu Jianxian Lin Jianliang Zheng Yongping Li 《Eye Science》 CAS 2011年第3期180-182,共3页
Ocular pathology serves as one vital branch subject of histopathology, and also as a basic ocular science analysing the pathogenesis of eye disease,the regular pattern of disease progress,and ocular morphology,tissue ... Ocular pathology serves as one vital branch subject of histopathology, and also as a basic ocular science analysing the pathogenesis of eye disease,the regular pattern of disease progress,and ocular morphology,tissue metabolism and functional changes noted during the onset of ocular diseases.The underlying purpose lies in revealing and investigating the mechanism of such diseases and the nature of lesions,providing essential theoretical evidence to diagnosis and treatment of eye diseases.ocular pathology acts as a bridge connecting basic and clinical medical science1.Clinical ophthalmologists,especially junior house staff,should attach importance to ocular pathology,understand,be familiar with,and master basic knowledge in ocular pathological subject to cultivate sound clinical thinking and analytical ability and to improve comprehensive diagnosis and treatment efficacy in clinical setting. 展开更多
关键词 组织病理学 眼部疾病 培养目标 临床 员工 眼科疾病 定位 发病机制
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New Argon Stopper Technology for Slab Casting
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作者 Gerald NITZL xiaohui liu +2 位作者 Qingxin liu Jie SHEN Yong TANG 《China's Refractories》 CAS 2021年第2期41-44,共4页
Argon addition into the casting channel reduces the amount of clogging on the refractory wall to allow long sequence casting of aluminium-killed steel grades.The key to minimum surface defects on the final product is ... Argon addition into the casting channel reduces the amount of clogging on the refractory wall to allow long sequence casting of aluminium-killed steel grades.The key to minimum surface defects on the final product is to establish the optimum quantity by optimising the gas distribution below the stopper nose.This is achieved by new argon stopper technology which supports low gas quantities with homogeneous gas and bubble distributions to float non-metallic inclusions(NMI)in the continuous casting mould. 展开更多
关键词 argon stopper technology slab casting aluminium-killed steel non-metallic inclusions
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Research and Optimization of Technological Process Based on Fermentation for Production of Seaweed Feed
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作者 Ling Han Shuping Zhang +1 位作者 Jie Ma xiaohui liu 《Green and Sustainable Chemistry》 2012年第2期47-54,共8页
This paper for the purpose of utilization, conducted a study of technological process of producing animal feed by fermenting seaweed waste. Anaerobic fermentation, which can improve the contents of protein and polysac... This paper for the purpose of utilization, conducted a study of technological process of producing animal feed by fermenting seaweed waste. Anaerobic fermentation, which can improve the contents of protein and polysaccharide in seaweed waste, proved to be an available method to improve the nutritional value of animal feed by using seaweed waste. Also effects of different additives and fermentation time on the fermentation products was compared, combined CCRD with neural network to optimize these factors, the predict model among all factors was established, also obtained the optimal fermentation process. 展开更多
关键词 ALGAE Waste ANAEROBIC FERMENTATION ANIMAL FEED
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