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COMPLEX WIENER-ITO CHAOS DECOMPOSITION REVISITED 预览
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作者 陈勇 刘勇 《数学物理学报:B辑英文版》 SCIE CSCD 2019年第3期797-818,共22页
In this article, some proper ties of complex Wiener-Ito multiple integrals and complex Ornstein-Uhlenbeck opera tors and semigroups are obtained. Those include Stroock's formula, Hu-Meyer formula, Clark-Ocone form... In this article, some proper ties of complex Wiener-Ito multiple integrals and complex Ornstein-Uhlenbeck opera tors and semigroups are obtained. Those include Stroock's formula, Hu-Meyer formula, Clark-Ocone formula, and the hypercontractivity of complex Ornstein-Uhlenbeck semigroups. As an application, several expansions of the fourth moments of complex Wiener-Ito multiple integrals are given. 展开更多
关键词 COMPLEX Hermite polynomials COMPLEX Gaussian isonormal processes COMPLEX Wiener-Ito Multiple INTEGRALS COMPLEX ORNSTEIN-UHLENBECK operators and SEMIGROUPS
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Polymer complexation for functional fibers
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作者 HUANG WenTao LIU DeZhong +2 位作者 LI JieFu ZHU LiPing YANG ShuGuang 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第6期931-944,共14页
Polymer complex is a polymer association of different polymers with good miscibility resulting from the relatively strong intermolecular interactions or stereo match effect between polymer chains. Polymer complexes ha... Polymer complex is a polymer association of different polymers with good miscibility resulting from the relatively strong intermolecular interactions or stereo match effect between polymer chains. Polymer complexes have been utilized in various fields, such as food, biomedical, cosmetic, and pharmacy. Fiber is one of the most important material forms, and shaping polymer complex into fiber will further extend its applications. This review briefly introduces the fundamentals of polymer complex, and then demonstrates the main approaches to produce polymer complex fibers(PCFs). Followed by, the modification of fibers with polymer complexes is presented. Finally, the applications of PCFs and the polymer complex modified fibers are provided, and the prospect of polymer complexation for fibers is discussed properly. 展开更多
关键词 interpolymer COMPLEX functional FIBER POLYELECTROLYTE COMPLEX HYDROGEN-BONDED polymer COMPLEX FIBER MODIFICATION
Involvement of T-complex protein 1-ring complex/chaperonin containing T-complex protein 1(TRiC/CCT)in retrograde axonal transport through tau phosphorylation 预览
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作者 Xu-Qiao Chen 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第4期588-590,共3页
The cytosolic chaperonin T-complex protein 1-ring complex(TRiC)or chaperonin containing T-complex protein 1(CCT)is essential in de novo folding of approximately 10%of the eukaryotic,newly translated polypeptides as we... The cytosolic chaperonin T-complex protein 1-ring complex(TRiC)or chaperonin containing T-complex protein 1(CCT)is essential in de novo folding of approximately 10%of the eukaryotic,newly translated polypeptides as well as misfolded proteins.There is a close link between the TRiC/CCT cytosolic chaperonin and neurodegenerative diseases(Lopez et al.,2015).A lot of research suggests that CCT plays neuroprotective roles in neurodegenerative diseases including Huntington’s disease(Lopez et al.,2015).Either overexpression of a single or all eight subunits(CCT1-8)or treatment of the substrate-binding apical domain of yeast CCT1(ApiCCT1)prevented mutant Huntingtin aggregation and improved cellular and neuronal functions(Zhao et al.,2016).Importantly,our recent study has demonstrated that both CCT and ApiCCT could reduce mutant Huntingtin level and enhance both anterograde and retrograde axonal transport of brain-derived neurotrophic factor.These results led to restoration of the trophic status of striatal neurons from a bacterial artificial chromosome transgenic mouse model of Huntington’s disease(Zhao et al.,2016).Axonal transport is regulated by many factors including microtubule-associated protein tau,which promotes tubulin polymerization and stabilizes microtubules.Impaired interaction between tau and microtubules plays a vital role in the pathogenesis of multiple neurodegenerative diseases(Wang and Mandelkow,2016).Interestingly,tau phosphorylation is also observed in brains of several Huntington’s disease mouse models and Huntington’s disease patients(Gratuze et al.,2016).In a recent study,we explored if CCT subunit has any effect on axonal transport in a tau-dependent pathway(Chen et al.,2018b).We focused on the retrograde axonal transport of brain-derived neurotrophic factor,as neurotrophic factor-mediated signaling in the form of signaling endosome is essential in both the developing and the mature nervous system and dysregulation of trafficking of neurotrophic factors is tightly linked to disorders of th 展开更多
关键词 T-COMPLEX PROTEIN 1-ring complex(TRiC) CHAPERONIN CONTAINING T-COMPLEX PROTEIN 1(CCT) Involvemen
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Two New Zn(Ⅱ) and Co(Ⅱ) Coordination Polymers Constructed by 4-Bromobenzoic Acid and 1,4-Bis(imidazol-1-yl)-butane: Synthesis, Crystal Structure and Theoretical Calculations 预览
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作者 潘亚茹 李秀梅 +2 位作者 刘博 周实 常鹰飞 《结构化学》 SCIE CAS CSCD 2019年第4期635-643,共9页
Two new coordination polymers, [Zn(bba)2(bib)]2n(1) and [Co0.5(bba)(bib)0.5]2n(2)(Hbba = 4-bromobenzoic acid, bib = 1,4-bis(imidazol-1-yl)-butane), have been hydrothermally designed and synthesized, and their structur... Two new coordination polymers, [Zn(bba)2(bib)]2n(1) and [Co0.5(bba)(bib)0.5]2n(2)(Hbba = 4-bromobenzoic acid, bib = 1,4-bis(imidazol-1-yl)-butane), have been hydrothermally designed and synthesized, and their structures were determined by elemental analyses, IR spectroscopy, TG, fluorescence spectroscopy, X-ray single-crystal and powder diffraction. Complexes 1 and 2 both belong to the monoclinic system and exhibit one-dimensional zigzag chain-like structure. In addition, we analyzed Natural Bond Orbital(NBO) in using the PBE0/LANL2 DZ method built in Gaussian 03 Program. The calculation results indicated the obvious covalent interaction between the coordinated atoms and Zn(Ⅱ), Co(Ⅱ) ions. 展开更多
关键词 SYNTHESIS crystal structure Zn(Ⅱ) COMPLEX Co(Ⅱ) COMPLEX natural bond orbital
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Identifying topologies and system parameters of uncertaintime-varying delayed complex networks
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作者 WANG Xiong GU HaiBo +1 位作者 WANG QianYao LU JinHu 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第1期94-105,共12页
Node dynamics and network topologies play vital roles in determining the network features and network dynamical behaviors.Thus it is of great theoretical significance and practical value to recover the topology struct... Node dynamics and network topologies play vital roles in determining the network features and network dynamical behaviors.Thus it is of great theoretical significance and practical value to recover the topology structures and system parameters of uncertain complex networks with available information. This paper presents an adaptive anticipatory synchronization-based approach to identify the unknown system parameters and network topological structures of uncertain time-varying delayed complex networks in the presence of noise. Moreover, during the identification process, our proposed scheme guarantees anticipatory synchronization between the uncertain drive and constructed auxiliary response network simultaneously. Particularly, our method can be extended to several special cases. Furthermore, numerical simulations are provided to verify the effectiveness and applicability of our method for reconstructing network topologies and node parameters. We hope our method can provide basic insight into future research on addressing reconstruction issues of uncertain realistic and large-scale complex networks. 展开更多
关键词 SYSTEM parameters and network TOPOLOGIES identification anticipatory synchronization UNCERTAIN time-varying delayed COMPLEX NETWORKS noise-perturbed COMPLEX NETWORKS
Pseudo-anti commuting Ricci tensor for real hypersurfaces in the complex hyperbolic quadric
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作者 Young Jin Suh 《中国科学:数学英文版》 SCIE CSCD 2019年第4期679-698,共20页
We introduce a new notion of pseudo-anti commuting Ricci tensor for real hypersurfaces in the noncompact complex hyperbolic quadric Q^m*= SO20,m/SO2SOm and give a complete classification of these hypersurfaces.
关键词 pseudo-anti COMMUTING Ricci tensor pseudo-Einstein A-isotropic A-principal COMPLEX conjugation COMPLEX HYPERBOLIC QUADRIC
Recurrent surgical site infection after anterior cruciate ligament reconstruction:A case report 预览
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作者 Don Koh Shi Ming Tan Andrew Hwee Chye Tan 《世界骨科杂志(英文版)》 2019年第6期255-261,共7页
BACKGROUND Surgical site infections following anterior cruciate ligament(ACL)reconstruction are an uncommon but potentially devastating complication.In this study,we present an unusual case of recurrent infection of t... BACKGROUND Surgical site infections following anterior cruciate ligament(ACL)reconstruction are an uncommon but potentially devastating complication.In this study,we present an unusual case of recurrent infection of the knee after an ACL reconstruction,and discuss the importance of accurate diagnosis and appropriate management,including the issue of graft preservation versus removal.CASE SUMMARY A 33-year-old gentleman underwent ACL reconstruction using a hamstring tendon autograft with suspensory Endobutton fixation to the distal femur and an interference screw fixation to the proximal tibia.Four years after ACL reconstruction,he developed an abscess over the proximal tibia and underwent incision and drainage.Remnant suture material was found at the base of the abscess and was removed.Five years later,he re-presented with a lateral distal thigh abscess that encroached the femoral tunnel.He underwent incision and drainage of the abscess which was later complicated by a chronic discharging sinus.Repeated magnetic resonance imaging revealed a fistulous communication between the lateral thigh wound extending toward the femoral tunnel with suggestion of osteomyelitis.Decision was made for a second surgery and the patient was counselled about the need for graft removal should there be intraarticular involvement.Knee arthroscopy revealed the graft to be intact with no evidence of intra-articular involvement.As such,the decision was made to retain the ACL graft.Re-debridement,excision of the sinus tract and removal of Endobutton was also performed in the same setting.Joint fluid cultures did not grow bacteria.However,tissue cultures from the femoral tunnel abscess grew Enterobacter cloacae complex,similar to what grew in tissue cultures from the tibial abscess five years earlier.In view of the recurrent and indolent nature of the infection,antibiotic therapy was escalated from Clindamycin to Ertapenem.He completed a six-week course of intravenous antibiotics and has been well for six months since surgery,with excellent 展开更多
关键词 Chronic SURGICAL SITE INFECTION Anterior CRUCIATE ligament reconstruction SURGICAL SITE INFECTION Graft preservation ENTEROBACTER CLOACAE complex Septic arthritis Case report
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Salamo型三核镍(Ⅱ)配合物的合成、晶体结构与Hirshfeld表面分析 预览
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作者 于盟 穆浩冉 +3 位作者 刘玲芝 李娜 白杨 董秀延 《无机化学学报》 SCIE CAS CSCD 北大核心 2019年第6期1109-1120,共12页
合成了2种新设计的Salamo型配合物,{[Ni(L1)(n-propanol)]2(OAc)2Ni}·2(n-propanol)(1)和{[Ni(L2)(n-butanol)]2(OAc)2Ni}·2(n-butanol)(2),并用元素分析、红外光谱、紫外-可见光谱、Hirshfeld表面分析和单晶X射线晶体学对其... 合成了2种新设计的Salamo型配合物,{[Ni(L1)(n-propanol)]2(OAc)2Ni}·2(n-propanol)(1)和{[Ni(L2)(n-butanol)]2(OAc)2Ni}·2(n-butanol)(2),并用元素分析、红外光谱、紫外-可见光谱、Hirshfeld表面分析和单晶X射线晶体学对其进行了表征。X射线晶体学分析表明,配合物1和2均为对称的三核镍(Ⅱ)配合物。1和2中的镍(Ⅱ)都是六配位的,形成了扭曲的八面体几何构型。晶体结构分析和Hirshfeld表面分析均表明,1和2通过分子间氢键作用分别形成稳定的一维链状和二维超分子结构。 展开更多
关键词 Salamo型配体 配合物 合成 晶体结构 Hirshfeld表面分析
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Comparison of Efficacy between 3D Navigation-Assisted Percutaneous Iliosacral Screw and Minimally Invasive Reconstruction Plate in Treating Sacroiliac Complex Injury 预览
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作者 Qi-lin LU Yi-liang ZHU +5 位作者 Xu-gui LI Wei XIE Xiao-zhen WANG Xue-zhen SHAO Xian-hua CAI Xi-ming LIU 《当代医学科学(英文)》 SCIE CAS 2019年第1期81-87,共7页
The clinical efficacy was compared between 3D navigation-assisted percutaneous iliosacral screw(3DPS)and minimally invasive reconstruction plate(MIRP)in treating sacroiliac complex injury and the surgical procedures o... The clinical efficacy was compared between 3D navigation-assisted percutaneous iliosacral screw(3DPS)and minimally invasive reconstruction plate(MIRP)in treating sacroiliac complex injury and the surgical procedures of 3DPS were introduced.A retrospective analysis was performed on 49 patients with sacroiliac complex injury from March 2013 to May 2017.Twenty-one cases were treated by 3DPS,and 28 cases by MIRP.Intraoperative indexes as operative time,blood loss,incision length,length of hospital stay and postoperative complications were respectively documented.Quality of reduction was postoperatively evaluated by Matta radiological criteria,and clinical effect was assessed by Majeed scoring criteria at the last followup.Operative time and hospital stay were significantly shortened,and blood loss,and incision length were significantly reduced in 3DPS group as compared with those in MIRP group(P<0.05).No statistically significant difference was found between 3DPS group and MIRP group in the assessment of reduction and function(P>0.05).It was concluded that both 3DPS and MIRP can effectively treat the sacroiliac complex injury,and 3DPS can provide an accurate,safe and minimally invasive fixation with shorter operative time and hospital stay. 展开更多
关键词 SACROILIAC complex injury 3D navigation-assisted system PERCUTANEOUS iliosacral SCREW MINIMALLY INVASIVE reconstruction plate
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Synthesis, Crystal Structure, and Fluorescent and Thermal Stability Properties of Two New Cobalt(Ⅱ) Complexes with 2,2’-Bipy as Ligand 预览
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作者 李玉林 杨颖群 +1 位作者 毛芳芳 陈志敏 《结构化学》 SCIE CAS CSCD 2019年第5期769-776,670共9页
Two new cobalt(Ⅱ)complexes[Co2(2,2?-bipy)2(dpa)2(H2O)5]·4H2O(1)and Co(2,2?-bipy)3(SO4)]·7.5H2O(2)have been synthesized with diaphonic acid(H2dpa)and 2,2?-bipyridine(2,2?-bipy)as ligands.In 1,two neighboring... Two new cobalt(Ⅱ)complexes[Co2(2,2?-bipy)2(dpa)2(H2O)5]·4H2O(1)and Co(2,2?-bipy)3(SO4)]·7.5H2O(2)have been synthesized with diaphonic acid(H2dpa)and 2,2?-bipyridine(2,2?-bipy)as ligands.In 1,two neighboring cobalt(Ⅱ)ions are linked together by one bridging diaphonic acid group,forming an asymmetric dinuclear structure.1 crystallizes in triclinic,space group P1 with a=9.825(6),b=13.007(8),c=19.586(1)A,α=80.773(1)o,β=77.065(1)o,γ=85.902(1)o,Mr=431.4,V=2406.5(3)A^3,Dc=1.48 g/cm^3,Z=2,μ(Mo Kα)=0.767 mm-1,F(000)=1112,the final R=0.0379 and wR=0.0862.The central cobalt(Ⅱ)ions in 1 and 2 are coordinated with six atoms,forming distorted octahedral coordination geometry.The fluorescence and thermal stability properties of 1 and 2 are also reported. 展开更多
关键词 cobalt(Ⅱ) complex crystal structure FLUORESCENCE thermal stability
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A New One-dimensional Complex Assembled by 4-Nitrobenzoic Acid and Bis(imidazol) Ligands:Syntheses, Structures and Theoretical Calculations 预览
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作者 李秀梅 潘亚茹 +2 位作者 刘博 周实 常鹰飞 《结构化学》 SCIE CAS CSCD 2019年第5期783-790,670共9页
A new Zn(Ⅱ)coordination polymer,[Zn(nba)2(mbix)]2n(1,Hnba=4-nitrobenzoic acid,mbix=1,3-bis(imidazol-1-ylmethyl)-benzene),was synthesized and characterized by elemental analyses,IR spectra,TG,fluorescence spectroscopy... A new Zn(Ⅱ)coordination polymer,[Zn(nba)2(mbix)]2n(1,Hnba=4-nitrobenzoic acid,mbix=1,3-bis(imidazol-1-ylmethyl)-benzene),was synthesized and characterized by elemental analyses,IR spectra,TG,fluorescence spectroscopy,single-crystal and powder X-ray diffractions.It belongs to the triclinic system,P1 space group,with a=9.341(2),b=13.029(3),c=23.660(6)A,α=99.603(6)°,β=90.461(6)°,γ=90.597(5)°,V=2838.9(12)?3 and Z=2.It shows one-dimensional chains which are further linked by C–H···O hydrogen bonds andπ-πstacking interactions to yield a three-dimensional supramolecular structure.In addition,the Natural Bond Orbital(NBO)was analyzed in using the PBE0/LANL2DZ method built in Gaussian 09 Program.The calculation results indicated obvious covalent interaction between the coordinated atoms and Zn(Ⅱ)ion. 展开更多
关键词 synthesis crystal structure 4-nitrobenzoic acid Zn(Ⅱ) complex natural BOND ORBITAL
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Manufacturing of High-efficiency Air Filter Paper Using Ultra-fine Fibers 预览
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作者 Yong-Chil Ro Yong-Il Ri Guang-Jin Jong 《造纸与生物质材料:英文版》 2019年第1期17-22,共6页
In this paper,the manufacturing of high-efficiency air filter paper is reported.The air filter paper was produced using ultra-fine fibers and wateroat fibers mercerized by alkali,using an electrospinning apparatus wit... In this paper,the manufacturing of high-efficiency air filter paper is reported.The air filter paper was produced using ultra-fine fibers and wateroat fibers mercerized by alkali,using an electrospinning apparatus with multiple rings.The high efficiency air filter paper has an antibacterial effect after adding a chitosan-copper complex which is harmless to humans.As a result of the measurement,the filtering efficiency of the air filter paper is approximately 99.998%and its antibacterial efficiency is approximately 99.5%. 展开更多
关键词 ultra-fine FIBER wateroat(Zizania latifolia)fiber chitosan-copper complex air filter paper
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一维Zn(Ⅱ)配合物{[Zn(Hpntc)2]·H2O}n的合成、结构及荧光性能研究
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作者 季甲 侯银玲 +2 位作者 韦胜艳 任晓玫 曾瑶 《化学试剂》 CAS 北大核心 2019年第1期84-88,共5页
以3,5-(4-羧酸苯基)-4-氨基-1,2,4-三氮唑为配体,六水合高氯酸锌为金属盐,通过水热合成法构筑了目标配合物。单晶结构解析表明该配合物属于三斜晶系,P-1空间群,单胞参数a=0. 800 79(12) nm,b=1. 136 01(11) nm,c=1. 636 91(16) nm,α=78... 以3,5-(4-羧酸苯基)-4-氨基-1,2,4-三氮唑为配体,六水合高氯酸锌为金属盐,通过水热合成法构筑了目标配合物。单晶结构解析表明该配合物属于三斜晶系,P-1空间群,单胞参数a=0. 800 79(12) nm,b=1. 136 01(11) nm,c=1. 636 91(16) nm,α=78. 070(8)°,β=81. 525(10)°,γ=84. 31(1)°。通过配体桥联,配合物形成一维链结构,再通过分子间氢键形成二维超分子结构。采用元素分析、红外光谱、粉末衍射对该配合物进行了表征,并研究了其室温下的固体荧光和乙醇溶液中的荧光性能。研究表明,配合物具有较强的荧光发射,是一种潜在的荧光材料。 展开更多
关键词 水热合成法 配合物 晶体结构 荧光
[CuI2(BBTP)]n的合成、晶体结构及抑菌活性 预览
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作者 高霞 潘会宾 +2 位作者 乔成芳 刘永亮 张国春 《陕西科技大学学报》 CAS 2019年第3期91-97,共7页
在溶剂热条件下设计并合成了1个结构新颖的功能配合物:[CuI2(BBTP)]n(1,BBTP=1,5-双(苯并三氮唑)戊烷).采用元素分析、X-射线粉末衍射、红外光谱、热分析以及固体荧光光谱等方法对配合物1进行了结构表征和性质研究.利用X-射线单晶衍射... 在溶剂热条件下设计并合成了1个结构新颖的功能配合物:[CuI2(BBTP)]n(1,BBTP=1,5-双(苯并三氮唑)戊烷).采用元素分析、X-射线粉末衍射、红外光谱、热分析以及固体荧光光谱等方法对配合物1进行了结构表征和性质研究.利用X-射线单晶衍射测定了配合物1的晶体结构,晶体属于三斜晶系,空间群为P-1,配体BBTP以μ3-桥联模式连接无机单元[Cu4I4]构成一维有机无机链,进而相邻的一维链又通过π-π作用堆积为二维层状结构,然后相邻的二维层状结构的芳环之间存在的π-π作用进一步使二维层堆积成三维超分子结构.采用菌落直径法研究了配合物1及其BBTP配体对腐皮镰刀真菌的抑菌效果,结果表明:配合物1及其BBTP配体对腐皮镰刀真菌的生长均具有一定的抑制作用. 展开更多
关键词 配合物 铜(I) 1 5-双(苯并三氮唑)戊烷 晶体结构 抑菌活性
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Visual analysis of the evolution and focus in landslide research field
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作者 YANG Jing CHENG Chang-xiu +2 位作者 SONG Chang-qing SHEN Shi NING Li-xin 《山地科学学报:英文版》 SCIE CSCD 2019年第5期991-1004,共14页
This paper analysed the evolution of landslide research and research foci in different countries. The data comprise 3105 landslide SCI articles published between January 1977 and June 2015 from the Web of Science. The... This paper analysed the evolution of landslide research and research foci in different countries. The data comprise 3105 landslide SCI articles published between January 1977 and June 2015 from the Web of Science. The data are extracted under interaction constraints of the journal title, category, and keywords. The complex network method is used for the analysis. First, from the perspective of topics and methods, the evolution is systematically assessed by generating a co-citation network of the articles and a semantic cluster analysis. Second, from the perspective of topics and landsliderelated disasters, the focus in different countries is discussed by generating co-occurrence networks. These networks are the co-occurrence of the countries and keywords, and the co-occurrence of countries and landslide-related disaster phrases. The main conclusions are as follows:(1) landslide susceptibility analysis and methods of machine learning are popular research topics and methods, respectively. The topics change through time, and the article output is influenced by increasing landslide-related disasters, increasing economic losses and casualties, a desire for a more complete and accurate landslide inventory, and the use of effective methods, such as geographical information Science(GIS) and machine learning.(2) The research focus in each country is related with the country-specific disasters or economic costs caused by landslides to some degree. In addition to Italy and the USA, China is the country most commonly affected by landslides, and it should develop its own landslide database and complete in-depth studies of disaster mitigation. 展开更多
关键词 LANDSLIDES COMPLEX network CLUSTER analysis EVOLUTION Research FOCUS
A New Hemi-and Holo-directed Lead(Ⅱ) Complex in Soft Ligand Environment 预览
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作者 谢璐璐 才华 +3 位作者 张阳 刘若冰 杨建辉 王欣怡 《结构化学》 SCIE CAS CSCD 2019年第5期803-810,671共9页
One new three-dimensional polymeric PbⅡ complex,[Pb3(CTA)2(H2 O)2]n·nH2O(1),(H3 CTA = cis,cis-1,3,5-cyclohexanetricarboxylic acid), has been synthesized. Single-crystal X-ray diffraction analyses reveal that com... One new three-dimensional polymeric PbⅡ complex,[Pb3(CTA)2(H2 O)2]n·nH2O(1),(H3 CTA = cis,cis-1,3,5-cyclohexanetricarboxylic acid), has been synthesized. Single-crystal X-ray diffraction analyses reveal that complex 1 has a three-dimensional architecture consisting of Pb2O2 dimeric building units, which shows two types of PbⅡ centers(eight-coordinated Pb(1),six-coordinated Pb(2) and Pb(3)). The eight-coordinated Pb(1) center possesses a stereochemically ‘inactive’ electron lone pair, and the coordination sphere is holodirected. However, the arrangement of oxygen atoms around Pb(2) and Pb(3) suggests a gap or hole in the coordination geometry. The stereo-chemically ‘active’ electron lone pairs of Pb(2) and Pb(3) possibly occupy these ‘holes’ and their coordination spheres are hemidirected. Its properties have been determined by FT-IR spectra, elemental analyses and thermogravimetric analyses(TGA). Solid-state luminescent properties of 1 also have been determined, indicating strong fluorescent emissions. 展开更多
关键词 lead(Ⅱ) complex SOLID-STATE LUMINESCENT holodirected hemidirected
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配合物[Cu(2,6-pidic)(H2O)2]2的晶体结构和磁性质 预览
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作者 张晓帆 曹慧 +3 位作者 郭帅 李成龙 高肖汉 吕雪川 《辽宁石油化工大学学报》 CAS 2019年第1期31-34,共4页
通过水热合成法合成了铜-2,6-吡啶二甲酸的配合物[Cu(2,6-pidic)(H2O)2]2的单晶,配合物属P-1空间群,晶胞参数为a=0.46992(2)nm、b=0.89320(3)nm、c=1.03036(6)nm。配合物分子互不连接,每个晶胞中含2个分子,中心铜离子为5配位。配合物的... 通过水热合成法合成了铜-2,6-吡啶二甲酸的配合物[Cu(2,6-pidic)(H2O)2]2的单晶,配合物属P-1空间群,晶胞参数为a=0.46992(2)nm、b=0.89320(3)nm、c=1.03036(6)nm。配合物分子互不连接,每个晶胞中含2个分子,中心铜离子为5配位。配合物的磁性质测试结果表明,中心铜离子间为反铁磁性作用。 展开更多
关键词 配合物 2 6-吡啶二甲酸 晶体结构 磁化率
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芹菜素-钆配合物的合成及其抗小鼠高尿酸血症研究
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作者 邢志华 姜婧雯 +4 位作者 王淑静 张秀娟 韩维娜 包然 张幸华 《中国稀土学报》 CAS CSCD 北大核心 2019年第1期114-120,共7页
将芹菜素(AP)与钆(III)离子配位生成配合物,以期提高芹菜素抗高尿酸血症活性。以具有一定抗炎、抗痛风活性的芹菜素为配体,以稀土金属钆(III)离子为配位中心,设计合成芹菜素-钆配合物(AP-Gd)。采用紫外(UV)、红外(IR)、氢核磁共振(1H-N... 将芹菜素(AP)与钆(III)离子配位生成配合物,以期提高芹菜素抗高尿酸血症活性。以具有一定抗炎、抗痛风活性的芹菜素为配体,以稀土金属钆(III)离子为配位中心,设计合成芹菜素-钆配合物(AP-Gd)。采用紫外(UV)、红外(IR)、氢核磁共振(1H-NMR)、电导法、 X射线光电子能谱(XPS)、差热-热重分析(TG-DTA)等技术对配合物的化学结构进行表征。考察配合物对酵母浸粉联合氧嗪酸钾诱导的高尿酸血症小鼠模型中尿酸、黄嘌呤氧化酶及超氧阴离子水平的影响。结果表明:芹菜素与钆(III)离子配位生成了配合物,配合物组成式为:[Gd(C15H9O5)2]·NO3·3H2O。芹菜素A环的5-OH和C环的4位C=O与钆(III)离子形成了配合物,且芹菜素与钆(III)离子的配位比为2。抗高尿酸症活性研究发现,芹菜素-钆配合物对高尿酸血症小鼠黄嘌呤氧化酶的抑制作用、清除超氧阴离子能力、降低血清尿酸水平及促进尿酸排泄能力均优于芹菜素,提示芹菜素与钆(III)离子配位后,所得配合物抗高尿酸血症活性增强。 展开更多
关键词 芹菜素 稀土 配合物 高尿酸血症 黄嘌呤氧化酶抑制剂
MCM-41负载钳形钯配合物的制备及其在α-芳基化反应的应用 预览
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作者 章文义 开旺 《应用化工》 CAS CSCD 北大核心 2019年第6期1287-1291,共5页
以MCM-41为载体,NCN钳形钯配合物为活性组分,以氨基甲酸酯和三乙氧基硅烷为联结基团,制备出负载型催化剂 NCN-Pd/MCM-41,采用 FTIR、XRD、氮气吸附仪对其进行了表征。结果表明,合成的催化剂具有介孔结构,无机载体和有机金属配合物均保... 以MCM-41为载体,NCN钳形钯配合物为活性组分,以氨基甲酸酯和三乙氧基硅烷为联结基团,制备出负载型催化剂 NCN-Pd/MCM-41,采用 FTIR、XRD、氮气吸附仪对其进行了表征。结果表明,合成的催化剂具有介孔结构,无机载体和有机金属配合物均保持了原有结构的完整性。将负载型催化剂应用于催化苯乙酮与溴苯的α-芳基化反应,考察了催化剂用量、反应时间和反应温度对产率的影响。结果表明,负载型催化剂 NCN-Pd/MCM-41在催化酮与溴苯的α-芳基化反应中表现出优异的催化活性,最优条件为:催化剂用量1.0%(摩尔分数),反应时间2h,反应温度81℃,在此条件下芳基化产物产率达到了90%,催化剂重复使用4次,产率仍在84%以上。 展开更多
关键词 MCM-41 配合物 α-芳基化 催化
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Asymmetric and Single-Side Splitting of Dissipative Solitons in Complex Ginzburg-Landau Equations with an Asymmetric Wedge-Shaped Potential
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作者 廖云程 刘彬 +1 位作者 刘娟 陈佳 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第1期24-27,共4页
We report some novel dynamical phenomena of dissipative solitons supported by introducing an asymmetric wedge-shaped potential (just as a sharp 'razor')into the complex Ginzburg-Landau equation with the cubicq... We report some novel dynamical phenomena of dissipative solitons supported by introducing an asymmetric wedge-shaped potential (just as a sharp 'razor')into the complex Ginzburg-Landau equation with the cubicquintic nonlinearity.The potentials corresponding to a local refractive index modulation with breaking symmetry can be realized in an active optical medium with respective expanding antiwaveguiding structures.Using the razor potential acting on a central dissipative soliton,possible outcomes of asymmetric and single-side splitting of dissipative solitons are achieved with setting different strengths and steepness of the potentials.The results can potentially be used to design a multi-route splitter for light beams. 展开更多
关键词 Dissipative SOLITONS Complex GINZBURG-LANDAU Equations ASYMMETRIC WEDGE-SHAPED POTENTIAL
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