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Structured Sparse Coding With the Group Log-regularizer for Key Frame Extraction 被引量:1
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作者 Zhenni Li Yujie Li +2 位作者 Benying Tan Shuxue Ding Shengli Xie 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第10期1818-1830,共13页
Key frame extraction based on sparse coding can reduce the redundancy of continuous frames and concisely express the entire video.However,how to develop a key frame extraction algorithm that can automatically extract ... Key frame extraction based on sparse coding can reduce the redundancy of continuous frames and concisely express the entire video.However,how to develop a key frame extraction algorithm that can automatically extract a few frames with a low reconstruction error remains a challenge.In this paper,we propose a novel model of structured sparse-codingbased key frame extraction,wherein a nonconvex group log-regularizer is used with strong sparsity and a low reconstruction error.To automatically extract key frames,a decomposition scheme is designed to separate the sparse coefficient matrix by rows.The rows enforced by the nonconvex group log-regularizer become zero or nonzero,leading to the learning of the structured sparse coefficient matrix.To solve the nonconvex problems due to the log-regularizer,the difference of convex algorithm(DCA)is employed to decompose the log-regularizer into the difference of two convex functions related to the l1 norm,which can be directly obtained through the proximal operator.Therefore,an efficient structured sparse coding algorithm with the group log-regularizer for key frame extraction is developed,which can automatically extract a few frames directly from the video to represent the entire video with a low reconstruction error.Experimental results demonstrate that the proposed algorithm can extract more accurate key frames from most Sum Me videos compared to the stateof-the-art methods.Furthermore,the proposed algorithm can obtain a higher compression with a nearly 18% increase compared to sparse modeling representation selection(SMRS)and an 8% increase compared to SC-det on the VSUMM dataset. 展开更多
关键词 Difference of convex algorithm(DCA) group logregularizer key frame extraction structured sparse coding
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Cost analysis of radical resection of malignant breast tumors under the China Healthcare Security Diagnosis Related Groups payment system
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作者 Yun-He Hu Ai-Dong Li 《World Journal of Clinical Cases》 SCIE 2024年第20期4174-4179,共6页
BACKGROUND Breast cancer is one of the most common malignant tumors in women worldwide and poses a severe threat to their health.Therefore,this study examined patients who underwent breast cancer surgery,analyzed hosp... BACKGROUND Breast cancer is one of the most common malignant tumors in women worldwide and poses a severe threat to their health.Therefore,this study examined patients who underwent breast cancer surgery,analyzed hospitalization costs and structure,and explored the impact of China Healthcare Security Diagnosis Related Groups(CHS-DRG)management on patient costs.It aimed to provide medical institutions with ways to reduce costs,optimize cost structures,reduce patient burden,and improve service efficiency.AIM To study the CHS-DRG payment system’s impact on breast cancer surgery costs.METHODS Using the CHS-DRG(version 1.1)grouping criteria,4073 patients,who underwent the radical resection of breast malignant tumors from January to December 2023,were included in the JA29 group;1028 patients were part of the CHS-DRG payment system,unlike the rest.Through an independent sample t-test,the length of hospital stay as well as total hospitalization,medicine and consumables,medical,nursing,medical technology,and management expenses were compared.Pearson’s correlation coefficient was used to test the cost correlation.RESULTS In terms of hospitalization expenses,patients in the CHS-DRG payment group had lower medical,nursing,and management expenses than those in the diagnosis-related group(DRG)non-payment group.For patients in the DRG payment group,the factors affecting the total hospitalization cost,in descending order of relevance,were medicine and consumable costs,consumable costs,medicine costs,medical costs,medical technology costs,management costs,nursing costs,and length of hospital stay.For patients in the DRG nonpayment group,the factors affecting the total hospitalization expenses in descending order of relevance were medicines and consumable expenses,consumable expenses,medical technology expenses,the cost of medicines,medical expenses,nursing expenses,length of hospital stay,and management expenses.CONCLUSION The CHS-DRG system can help control and reduce unnecessary medical expenses by controlling medicine costs,medical consumable costs,and the length of hospital stay while ensuring medical safety. 展开更多
关键词 China Healthcare Security Diagnosis Related groups Real-world study Radical resection of malignant breast tumors Hospitalization costs Cost structure Average length of stay
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Surgical treatment of liver cancer and pancreatic cancer under the China Healthcare Security Diagnosis Related Groups payment system
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作者 Yun-He Hu Fan Yu +1 位作者 Yu-Zhuo Zhou Ai-Dong Li 《World Journal of Clinical Cases》 SCIE 2024年第21期4673-4679,共7页
BACKGROUND Data from the World Health Organization’s International Agency for Research on Cancer reported that China had the highest prevalence of cancer and cancer deaths in 2022.Liver and pancreatic cancers account... BACKGROUND Data from the World Health Organization’s International Agency for Research on Cancer reported that China had the highest prevalence of cancer and cancer deaths in 2022.Liver and pancreatic cancers accounted for the highest number of new cases.Real-world data(RWD)is now widely preferred to traditional clinical trials in various fields of medicine and healthcare,as the traditional research approach often involves highly selected populations and interventions and controls that are strictly regulated.Additionally,research results from the RWD match global reality better than those from traditional clinical trials.AIM To analyze the cost disparity between surgical treatments for liver and pancreatic cancer under various factors.METHODS This study analyzed RWD 1137 cases within the HB1 group(patients who underwent pancreatectomy,hepatectomy,and/or shunt surgery)in 2023.It distinguished different expenditure categories,including medical,nursing,technical,management,drug,and consumable costs.Additionally,it assessed the contribution of each expenditure category to total hospital costs and performed cross-group comparisons using the non-parametric Kruskal–Wallis test.This study used the Steel–Dwass test for post-hoc multiple comparisons and the Spearman correlation coefficient to examine the relationships between variables.RESULTS The study found that in HB11 and HB13,the total hospitalization costs were significantly higher for pancreaticoduodenectomy than for pancreatectomy and hepatectomy.Although no significant difference was observed in the length of hospital stay between patients who underwent pancreaticoduodenectomy and pancreatectomy,both were significantly longer than those who underwent liver resection.In HB15,no significant difference was observed in the total cost of hospitalization between pancreaticoduodenectomy and pancreatectomy;however,both were significantly higher than those in hepatectomy.Additionally,the length of hospital stay was significantly longer for patients who underwent pancreaticoduodenectomy than for those who underwent pancreatectomy or liver resection.CONCLUSION China Healthcare Security Diagnosis Related Groups payment system positively impacts liver and pancreatic cancer surgeries by improving medical quality and controlling costs.Further research could refine this grouping system and ensure continuous effectiveness and sustainability. 展开更多
关键词 China health care security diagnosis-related groups Real-world study Liver cancer surgical treatment Pancreatic cancer surgical treatment Hospitalization costs Cost structure Average length of stay
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Discussion on the Complex Structure of Nilpotent Lie Groups Gk
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作者 Caiyu Du Yu Wang 《Open Journal of Applied Sciences》 2024年第6期1401-1411,共11页
Consider the real, simply-connected, connected, s-step nilpotent Lie group G endowed with a left-invariant, integrable almost complex structure J, which is nilpotent. Consider the simply-connected, connected nilpotent... Consider the real, simply-connected, connected, s-step nilpotent Lie group G endowed with a left-invariant, integrable almost complex structure J, which is nilpotent. Consider the simply-connected, connected nilpotent Lie group Gk, defined by the nilpotent Lie algebra g/ak, where g is the Lie algebra of G, and ak is an ideal of g. Then, J gives rise to an almost complex structure Jk on Gk. The main conclusion obtained is as follows: if the almost complex structure J of a nilpotent Lie group G is nilpotent, then J can give rise to a left-invariant integrable almost complex structure Jk on the nilpotent Lie group Gk, and Jk is also nilpotent. 展开更多
关键词 Almost Complex Structure Nilpotent Lie group Nilpotent Lie Algebra
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Network autoregression model with grouped factor structures
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作者 ZHANG Zhiyuan ZHU Xuening 《中山大学学报(自然科学版)(中英文)》 CAS CSCD 北大核心 2023年第5期24-37,共14页
Network autoregression and factor model are effective methods for modeling network time series data.In this study,we propose a network autoregression model with a factor structure that incorporates a latent group stru... Network autoregression and factor model are effective methods for modeling network time series data.In this study,we propose a network autoregression model with a factor structure that incorporates a latent group structure to address nodal heterogeneity within the network.An iterative algorithm is employed to minimize a least-squares objective function,allowing for simultaneous estimation of both the parameters and the group structure.To determine the unknown number of groups and factors,a PIC criterion is introduced.Additionally,statistical inference of the estimated parameters is presented.To assess the validity of the proposed estimation and inference procedures,we conduct extensive numerical studies.We also demonstrate the utility of our model using a stock dataset obtained from the Chinese A-Share stock market. 展开更多
关键词 network autoregression factor structure HETEROGENEITY latent group structure network time series
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Improvisation of Node Mobility Using Cluster Routing-based Group Adaptive in MANET
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作者 J.Shanthini P.Punitha S.Karthik 《Computer Systems Science & Engineering》 SCIE EI 2023年第3期2619-2636,共18页
In today's Internet routing infrastructure,designers have addressed scal-ing concerns in routing constrained multiobjective optimization problems examining latency and mobility concerns as a secondary constrain.In... In today's Internet routing infrastructure,designers have addressed scal-ing concerns in routing constrained multiobjective optimization problems examining latency and mobility concerns as a secondary constrain.In tactical Mobile Ad-hoc Network(MANET),hubs can function based on the work plan in various social affairs and the internally connected hubs are almost having the related moving standards where the topology between one and the other are tightly coupled in steady support by considering the touchstone of hubs such as a self-sorted out,self-mending and self-administration.Clustering in the routing process is one of the key aspects to increase MANET performance by coordinat-ing the pathways using multiple criteria and analytics.We present a Group Adaptive Hybrid Routing Algorithm(GAHRA)for gathering portability,which pursues table-driven directing methodology in stable accumulations and on-request steering strategy for versatile situations.Based on this aspect,the research demonstrates an adjustable framework for commuting between the table-driven approach and the on-request approach,with the objectives of enhancing the out-put of MANET routing computation in each hub.Simulation analysis and replication results reveal that the proposed method is promising than a single well-known existing routing approach and is well-suited for sensitive MANET applications. 展开更多
关键词 Diplomatic mobile Ad-hoc network grouping mobility interior stable hybrid routing scheme adaptive switch structure clustering communication
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Construction of some hypergroups from combinatorial structures
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作者 AliRezaAshrafi AhmadRezaEslami-Harandi 《Journal of Zhejiang University Science》 CSCD 2003年第1期76-79,共4页
Jajcay's studies( 1993 ; 1994) on the automorphism groups of Cayley maps yielded a new product of groups, which he called, rotary product. Using this product, we define a hyperoperation ⊙ on the group Syme (G) , ... Jajcay's studies( 1993 ; 1994) on the automorphism groups of Cayley maps yielded a new product of groups, which he called, rotary product. Using this product, we define a hyperoperation ⊙ on the group Syme (G) , the stabilizer of the identity e ∈ G in the group Sym (G) . We prove that ( Syme (G) , ⊙) is a hypergroup and characterize the subhypergroups of this hypergroup.Finally, we show that the set of all subhypergroups of Syme ( G ) constitute a lattice under ordinary join and meet and that the minimal elements of order two of this lattice is a subgroup of Aut (G) . 展开更多
关键词 Finite group Rotary closed subgroup HYPERgroup Sub hypergroup Combinatorial structures
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Finite Abelian Group of | A(G) |= 27pq 被引量:2
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作者 Huang Benwen (Department of Mathematics,Wuhan University, Wuhan 430072,China ) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第1期25-30,共6页
we have discussed structures of Abelian group G by order |A(G) |of automoorphism group and have obtained all types of finite Abelian grooup G when the order of A(G) equals 27pq(p,q are odd primmes).
关键词 Abelian group automorphism group structure of group
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The Influence of Primitive Subgroups on the Structure of Finite Groups
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作者 Liu Yu-feng Du Xian-kun 《Communications in Mathematical Research》 CSCD 2013年第2期179-183,共5页
A subgroup H of a group G is said to be primitive if it is a proper subgroup of the intersection of all subgroups of G containing H as its proper subgroup. The purpose of this note is to go further into the influence ... A subgroup H of a group G is said to be primitive if it is a proper subgroup of the intersection of all subgroups of G containing H as its proper subgroup. The purpose of this note is to go further into the influence of primitive subgroups on the structure of finite groups. Some new results are obtained. 展开更多
关键词 primitive subgroup supersoluble group structure of group
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The Relationship of Between Fuzzy Power Groups and Fuzzy Quotient Groups
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作者 YAN Guang-xia MI Hong-hai SHI Ya-ting 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第4期493-496,共4页
In this paper, we extend the concept of fuzzy quotient groups. The structuresof fuzzy power groups and fuzzy quotient groups are discussed. The relationship betweenfuzzy power groups and fuzzy quotient groups are cons... In this paper, we extend the concept of fuzzy quotient groups. The structuresof fuzzy power groups and fuzzy quotient groups are discussed. The relationship betweenfuzzy power groups and fuzzy quotient groups are considered. 展开更多
关键词 group power group UPGRADE fuzzy power group mathematics structure
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Attribution retraining group therapy for outpatients with major depression disorder,generalized anxiety disorder,and obsessive-compulsive disorder:a pilot study 被引量:7
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作者 Chun Wang Jie Zhang +2 位作者 Jijun Li Ning Zhang Yalin Zhang 《The Journal of Biomedical Research》 CAS 2011年第5期348-355,共8页
The aim of this present study is to examine the efficacy of attribution retraining group therapy (ARGT) and to compare the responses of outpatients with major depression disorder (MDD), generalized anxiety disord... The aim of this present study is to examine the efficacy of attribution retraining group therapy (ARGT) and to compare the responses of outpatients with major depression disorder (MDD), generalized anxiety disorder (GAD) and obsessive-compulsive disorder (OCD). We carried out a prospective uncontrolled intervention study with a 8-weeks of ARGT on sixty three outpatients with MDD, GAD or OCD. Hamilton rating scale for depression, Hamilton rating scale for anxiety, Yale-Brown obsessive-compulsive scale, attribution style questionnaire, self-esteem scale, index of well-being, and social disability screening schedule were administered before and after treatment. Significant improvement in symptoms and psychological and social functions from pre- to posttreatment occurred for all participants. The changes favored MDD patients. Our study suggested that ARGT may improve the symptoms and psychological-social functions of MDD, GAD, and OCD patients. MDD patients showed the best response. 展开更多
关键词 attribution retraining group psychotherapy major depression disorder generalized anxiety disorder obsessive-compulsive disorder
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Nurse-led group cognitive behavioral therapy for major depressive disorder among adults in Japan: A preliminary single-group study 被引量:2
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作者 Hiroki Tanoue Naoki Yoshinaga +3 位作者 Sayaka Kato Keiko Naono-Nagatomo Yasushi Ishida Yuko Shiraishi 《International Journal of Nursing Sciences》 2018年第3期218-222,共5页
Objectives:The prevalence and burden of disease of depression necessitates effective and accessible treatment options worldwide.Since April 2016,Japanese national health insurance has covered nurseadministered cogniti... Objectives:The prevalence and burden of disease of depression necessitates effective and accessible treatment options worldwide.Since April 2016,Japanese national health insurance has covered nurseadministered cognitive behavioral therapy(CBT)for mood disorders.However,empirical support for nurse-led CBT for depression in Asian countries,especially in Japan,is still lacking.This preliminary study aimed to examine the feasibility and acceptability of nurse-led group CBT for Japanese patients with depression.Methods:In this single-arm study,we evaluated the effects of a 6-week group CBT,led by trained nurses,on patients with major depression.The primary outcome was the Beck Depression Inventory-Ⅱ(BDI-Ⅱ).Assessments were conducted at the beginning and end of the intervention.Results:Of 25 participants screened,23 were eligible for the study(of these,three dropped out during the trial but were included in the analysis).Nurse-led group CBT led to significant improvements in the severity of depression(BDI-Ⅱ,P<0.001).The mean total BDI-Ⅱscore improved from 23.1(SD=7.56)to 12.4(SD=8.57),and the pre-to post-effect size was large(Cohen's d=1.33).After CBT,45%of the participants were judged to be treatment responders,and 34%met the remission criteria.Conclusions:Our preliminary findings indicate that 6 weeks of nurse-led group CBT produced a favorable treatment outcome for individuals with major depression in a Japanese clinical setting.The results of this study might encourage more Asian nurses to provide CBT as a part of their nursing practice.Further controlled trials that address the limitations of this study are required. 展开更多
关键词 Behavior therapy Cognitive therapy Depressive disorder group psychotherapy Nursing care
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On Direct Product of HX Groups 被引量:3
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作者 米洪海 曾文艺 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第4期1-5, ,共5页
In the paper [1] the upgrade of the structure of groups has been considered, in which the concept of HX group has been raised. In this paper we will discuss the direct product of HX groups and AX groups on direct prod... In the paper [1] the upgrade of the structure of groups has been considered, in which the concept of HX group has been raised. In this paper we will discuss the direct product of HX groups and AX groups on direct product group. 展开更多
关键词 HX group structure of group direct product
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Coset Structure of Spin Group 被引量:1
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作者 WANG Na WU Ke 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第6期987-994,共8页
This article considers One example is also given to take a the coset structure closer look at what of spin group via analyzing the expression of its representation. the coset and the subgroup are.
关键词 spin group group representation coset structure
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Brief Analysis of Group Structure in the Language Classroom
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作者 赵丹晨 《海外英语》 2013年第3X期218-220,共3页
Group activities are commonly used in second language classroom in recent years mostly because they encourage students to work together,helping each other.However,it is of great importance for teachers to notice the g... Group activities are commonly used in second language classroom in recent years mostly because they encourage students to work together,helping each other.However,it is of great importance for teachers to notice the group structures so that this class activity could play its important role in the classroom. 展开更多
关键词 group STRUCTURE COOPERATIVE
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Group velocity distribution of Rayleigh waves and crustal and upper mantle velocity structure of the Chinese mainland and its vicinity 被引量:5
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作者 何正勤 丁志峰 +2 位作者 叶太兰 孙为国 张乃铃 《Acta Seismologica Sinica(English Edition)》 CSCD 2002年第3期269-275,共7页
Based on the long period digital surface wave data recorded by 11 CDSN stations and 11 IRIS stations, the dispersion curves of the group velocities of fundamental mode Rayleigh waves along 647 paths, with the periods ... Based on the long period digital surface wave data recorded by 11 CDSN stations and 11 IRIS stations, the dispersion curves of the group velocities of fundamental mode Rayleigh waves along 647 paths, with the periods from 10 s to 92 s, were measured by multi-filter. Their distribution at 25 central periods within the region of 18~54N, 70~140E was inverted by Dimtar-Yanovskaya method. Within the period from 10 s to 15.9 s, the group velocity distribution is laterally inhomogeneous and is closely related to geotectonic units, with two low velocity zones located in the Tarim basin and the East China Sea and its north regions, respectively. From 21 s to 33 s, the framework of tectonic blocks is revealed. From 36.6 s to 40 s, the lithospheric subdivision of the Chinese mainland is obviously uncovered, with distinct boundaries among the South-North seismic belt, the Tibetan plateau, the North China, the South China and the Northeast China. Four cross-sections of group velocity distribution with period along 30N, 38N, 90E and 120E, are discussed, respectively, which display the basic features of the crust and upper mantle of the Chinese mainland and its neighboring regions. There are distinguished velocity differences among the different tectonic blocks. There are low-velocity-zones (LVZ) in the middle crust of the eastern Tibetan plateau, high velocity featured as stable platform in the Tarim basin and the Yangtze platform, shallow and thick low-velocity-zone in the upper mantle of the North China. The upper mantle LVZ in the East China Sea and the Japan Sea is related to the frictional heat from the subduction of the Philippine slab and the strong extension since the Himalayan orogenic period. 展开更多
关键词 Rayleigh wave group velocity distribution crust and upper mantle velocity structure
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Molecular reconstruction model based on structure oriented lumping and group contribution methods 被引量:7
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作者 Jincai Chen Zhou Fang Tong Qiu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第8期1677-1683,共7页
Molecular management is a promising technology to face challenges in the refining industry, such as more stringent requirements for product oil and heavier crude oil, and to maximize the value of every molecule in pet... Molecular management is a promising technology to face challenges in the refining industry, such as more stringent requirements for product oil and heavier crude oil, and to maximize the value of every molecule in petroleum fractions. To achieve molecular management in refining processes, a novel model that is based on structure oriented lumping(SOL) and group contribution(GC) methods was proposed in this study. SOL method was applied to describe a petroleum fraction with structural increments, and GC method aimed to estimate molecular properties. The latter was achieved by associating rules between SOL structural increments and GC structures. A three-step reconstruction algorithm was developed to build a representative set of molecules from partial analytical data. First, structural distribution parameters were optimized with several properties. Then, a molecular library was created by using the optimized parameters. In the final step, maximum information entropy(MIE) method was applied to obtain a molecular fraction. Two industrial samples were used to validate the method, and the simulation results of the feedstock properties agreed well with the experimental data. 展开更多
关键词 Molecular reconstruction Structure oriented lumping group contribution Monte Carlo Maximum information entropy
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Two New Main Group Metal Coordination Polymers Based on 2,5-Furandicarboxylic Acid: Syntheses and Crystal Structures 被引量:2
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作者 王浩 刘洋 +2 位作者 陈飞 郭雨萌 章应辉 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第4期585-593,共9页
By using solvothermal method, two new main group metal coordination polymers based on 2,5-furandicarboxylic acid (H2FDA) ligand, [Sr2(FDA)E(H2O)5]n (1) and [Ba4(FDA)4(H2O)10]n (2), were produced and char... By using solvothermal method, two new main group metal coordination polymers based on 2,5-furandicarboxylic acid (H2FDA) ligand, [Sr2(FDA)E(H2O)5]n (1) and [Ba4(FDA)4(H2O)10]n (2), were produced and characterized by single-crystal X-ray diffraction analyses, elemental analyses, IR, and powder X-ray diffraction. Compound 1 crystallizes in monoclinic, space group C2/c with a = 13.454(3), b = 13.426(3), c = 20.166(4) A, β = 107.06(3)°, V = 3482.4(13)A^3, Dc = 2.188 g/cm^3, CIEH14Sr2O15, Mr = 573.47, F(000) = 2256,μ(MoKα)= 6.21 mm^-1, Z = 8, R = 0.0522 and wR = 0.1229 for 2493 observed reflections (I〉 2σ(I)), and R = 0.0689 and wR = 0.1324 for all data. Compound 2 crystallizes in triclinic, space group el with α = 6.8382(14), b = 10.932(2), c = 25.571(5) A,α = 94.64(3), β= 95.41(3), γ = 107.83(3)°, V= 1799.4(6) A3, Dc = 2.484 g/cm^3, C24H28Ba4O30, Mr = 1345.82, F(000) = 1272,μ(MoKa) = 4.43 mm^-1, Z = 2, R = 0.0485 and wR = 0.0906 for 5020 observed reflections (I〉 2σ(I)), and R = 0.0706 and wR = 0.0991 for all data. In 1, the trinuclear clusters Sr3 are connected with adjacent four clusters by a carboxylate group to produce a two-dimensional (2D) sheet, which is extended by a FDA-based pillar into a 3D framework. In 2, neighbouring trinuclear clusters Ba3 are linked through two -O-C-O- of FDA^2- ligands to form one-dimensional (1D) chains, which are connected by a FDA-based pillar to construct a 2D framework. The thermal stabilities of 1 and 2 are also investigated. 展开更多
关键词 2 5-furandicarboxylic acid main group crystal structure
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Board-invited review: Sensitivity and responses of functional groups to feed processing methods on a molecular basis 被引量:2
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作者 Peiqiang Yu 《Journal of Animal Science and Biotechnology》 SCIE CAS 2013年第1期1-4,共4页
In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore... In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore produce unique molecular vibration spectral profile. Feed processing has been used to improve nutrient utilization for many years. However, to date, there was little study on processing-induced changes of feed intrinsic structure and functional groups on a molecular basis within intact tissue. This is because limited research technique is available to study inherent structure on a molecular basis. Recently bioanalytical techniques: such as Synchrotron Infrared Microspectroscopy as well as Diffuse Reflectance Infrared Fourier Transform molecular spectroscopy have been developed. These techniques enable to detect molecular structure change within intact tissues. These techniques can prevent destruction or alteration of the intrinsic protein structures during processing for analysis. However, these techniques have not been used in animal feed and nutrition research. The objective of this review was show that with the advanced technique, sensitivity and responses of functional groups to feed processing on a molecular basis could be detected in my research team. These functional groups are highly associated with nutrient utilization in animals. 展开更多
关键词 Sensitivity and responses of functional groups Molecular structures Feed processing Nutrient utilizationand availability
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Crystal Chemistry Research of Minerals of Nigerite Group and Its Significance 被引量:2
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作者 CbenJingzhong WangFang +2 位作者 HanWei ZhangRonghong PengJue 《Journal of China University of Geosciences》 SCIE CSCD 2003年第4期293-299,共7页
There is a type of complex oxide mineral, composed of many elements such as Sn, Mg, Fe, Zn, Ti, Mn, Al, etc., in the areas of Anhua, Linwu and Shizhuyuan of Hunan Province. These minerals belong to nigerite, Mg-nigeri... There is a type of complex oxide mineral, composed of many elements such as Sn, Mg, Fe, Zn, Ti, Mn, Al, etc., in the areas of Anhua, Linwu and Shizhuyuan of Hunan Province. These minerals belong to nigerite, Mg-nigerite (pengzhizhongite), etc.. According to the principle of closest packing, the crystal chemical properties of nigerite (brown), pengzhizhongite (buff), Zn-nigerite (fawn), Fe-nigerite, Mn-nigerite (greenish-black) etc. have been analyzed. Their crystal structures may be characterized by O (the layers of cation octahedral coordinations), T_1 (the mixed layers of cation octahedral coordinations and cation tetrahedral coordinations in same directions), T_2 (the mixed layers of cation octahedral coordinations and cation tetrahedral coordination in different directions). The position of layer-O and layer-T is alternate permutation. The crystal structure of pengzhizhongite (6 H ) may be expressed by …OT_2OT_1OT_1…, taaffeite (8 H ), …OT_2OT_1OT_2OT_1…, and nigerite (24 R ), … OT_1OT_2 OT_2OT_1 …×3 etc.. In their structure, there are not only the crystal structure units of spinel … OT_2 OT_2 … but also the units of nolanite … OT_1 OT_1 …. The research of these minerals has important theoretic and practical significance in the fields of minerals, gemology, material science etc.. 展开更多
关键词 oxide of nigerite group crystal structure crystal chemistry new mineral new polytype gemology material science.
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