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Peplau's interpersonal relationship theory combined with bladder function training on patients with prostate cancer 被引量:4
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作者 Xiao-Hui Yang Li-Fen Wu +2 位作者 Xiao-Yu Yan Ying Zhou Xue Liu 《World Journal of Clinical Cases》 SCIE 2022年第9期2792-2800,共9页
BACKGROUND Prostate cancer is a major disease impacting men’s health worldwide.Peplau,who is known as“the mother of psychiatric society,”developed an interpersonal relationship theory for nursing.Implementation of ... BACKGROUND Prostate cancer is a major disease impacting men’s health worldwide.Peplau,who is known as“the mother of psychiatric society,”developed an interpersonal relationship theory for nursing.Implementation of this theory in practice has been shown to positively impact patients’quality of life and reduce adverse symptoms after surgery.AIM To investigate the effects of a nursing model based on Peplau’s interpersonal relationship theory combined with bladder function training on patients with prostate cancer.METHODS Eighty-nine patients with prostate cancer who underwent transurethral resection of the prostate(TURP)participated in this study.These patients were admitted to The First Affiliated Hospital of Soochow University or Dushu Lake Hospital Affiliated to Soochow University between January 2020 and April 2021.Patients were randomized into either the Peplau nursing group(n=44)or a routine nursing group(n=45).The routine nursing group received routine care and bladder function training,while the Peplau care group received care that integrated concepts from the Peplau interpersonal relationship theory as well as bladder function training.The urinary incontinence symptoms of the two groups were recorded,and the respective International Prostate Symptom Scores(IPSS),Functional Assessment of Chronic Illness Therapy-Spiritual Well-Being(FACIT-Sp)scores,and quality of life(QOL)scores for each group were compared before and after three months of nursing intervention.RESULTS During the intervention period,the duration of urinary incontinence,frequency,number and amount of urinary incontinence were significantly greater in the routine nursing group compared to the Peplau care group(P<0.05).The indicators of the routine nursing group were 7.13±2.42 days,8.23±2.75 times,and 1.24±0.42 L,while those of the Peplau care group were 4.74±1.85 d,4.21±1.26 times,and 0.56±0.11 L,respectively.After three months of intervention,the mean IPSS score of the routine nursing group was significantly reduced(P<0.05),while the mean FACIT-Sp and QOL scores were significantly increased(P<0.05).The mean IPSS score in the Peplau nursing group was significantly lower compared to the routine nursing group,while the FACIT-Sp and QOL scores were higher(P<0.05).CONCLUSION A nursing model based on Peplau’s interpersonal relationship theory combined with bladder function training can significantly improve prostate function and urinary symptoms,resulting in the restoration of physiological function and improvement in the QOL of patients with prostate cancer following TURP. 展开更多
关键词 Peplau interpersonal relationship theory Bladder function training Prostate cancer Quality of life NURSING
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Study on Principal-agent Mechanism in Chinese Private Enterprises 被引量:1
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作者 Xu Ren Ziheng Huang 《Chinese Business Review》 2005年第1期59-63,共5页
Based on the principal-agent theory, this paper analyzes the current situation and the developing trends of Chinese private enterprises. It points out the obstacles confronted by Chinese private enterprise in setting ... Based on the principal-agent theory, this paper analyzes the current situation and the developing trends of Chinese private enterprises. It points out the obstacles confronted by Chinese private enterprise in setting up the principal-agent mechanism and proposes the corresponding solutions to these problems. 展开更多
关键词 private enterprise principal-agent theory incentive constraints mechanism
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Relationship among Teacher,Students and Teaching Material based on Balance Theory
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作者 张筠 《海外英语》 2012年第19期113-115,共3页
Balance theory holds that when the subject is in the unbalanced state,there is two basic way to eliminate this situation.One is to change his attitude on the cognitive object;the other is to change the subject's a... Balance theory holds that when the subject is in the unbalanced state,there is two basic way to eliminate this situation.One is to change his attitude on the cognitive object;the other is to change the subject's attitude on reference person.To ex plain the relationship among teacher,students and teaching material by applying the Balance theory can help us find and solve problems during the education.It can generate motivation to restore a new balance to promote the development of education. 展开更多
关键词 BALANCE theory relationship EDUCATION development
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Development of the Emerging Theory of Encountering Nursing in a Nurse-Nursed Dyadic Relationship (ThENNDyR)
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作者 Jose Mari Louis Alforque Raza Crecia Meneses +1 位作者 Miralou Sorronda Rozzano C. Locsin 《Open Journal of Nursing》 2020年第9期777-809,共33页
Encounters are celebrated experiences between persons with connectedness in human situations as expectation. While being in a human dynamic and rhythmic interaction, nursing encounters are dyadic relationships illumin... Encounters are celebrated experiences between persons with connectedness in human situations as expectation. While being in a human dynamic and rhythmic interaction, nursing encounters are dyadic relationships illuminated as patterns of an interconnected relationship moving between the nurse and the nursed, and reflecting person-and-otherness events. The purpose of this paper is to describe the theory of Encountering Nursing in a Nurse-Nursed Dyadic Relationship (ThENNDyR) and to illuminate the four nursing practice processes on which the theory is founded: <em>Knowing as appreciating relational moments</em>;<em>Reflecting as engaging moments</em>;<em>Realizing as patterns of living moments</em>;and <em>Transcending as celebrating moments</em>. Nursing practice occurs in moments in which dyadic relationships transpire as nursing encounters. As fleeting as moments are, the four processes of nursing simultaneously take place as understanding conditions that the <em>who</em> and <em>what</em> of the person warrants persons. “Encountering nursing” is a momentary co-existence of persons in a person-and-otherness situation communicating connectedness-interconnectedness in distinct patterning. Interactions in nursing exist as persons remain wholes and complete in the moment. 展开更多
关键词 Dyadic relationship KNOWING Nursing Encounter Reflecting Transcending Nursing theory Nursing Practice
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SCM Implementation Decisions of Principal-Agent under Asymmetric Information
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作者 Lina Wang Stephan Poelmans Koen Milis 《Open Journal of Applied Sciences》 2019年第4期159-171,共13页
The optimization investment policy decision of SCM-Supply Chain Management-implementation has been analysed under symmetric and asymmetric information conditions. For both conditions, SCM implementation options’ deci... The optimization investment policy decision of SCM-Supply Chain Management-implementation has been analysed under symmetric and asymmetric information conditions. For both conditions, SCM implementation options’ decision optimizing models have been developed. In these models, both clients and vendors try to pursue their own benefits. Based upon the principal-agent theory, the models show to what extent a principal (a client) needs to pay more to an agent (a vendor) in a context of asymmetric information. For the client, it is important to understand the extra costs to be able to adopt effective strategies to stimulate a vendor to perform an optimal implementation of a SCM system. The results of a simulation experiment regarding SCM implementation options illustrate and verify the theoretical findings and confirm the general notion that the less informed party is obliged to pay information rent to the better-informed party. 展开更多
关键词 SCM IMPLEMENTATION PROBLEMS ASYMMETRIC Information IMPLEMENTATION Control COST Evaluation Level principal-agent theory
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On Sino-U.S. Economic and Trade Relationship And the Trend of Its Future Development——A Refutation of the “Theory of China’s Economic Threat”
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作者 Yin Chengde 《China International Studies》 2006年第1期85-101,共17页
关键词 theory of China s Economic Threat A Refutation of the Economic and Trade relationship And the Trend of Its Future Development On Sino-U.S
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On Ethical Literary Criticism and Game Theory--An Interview with Professor Nie Zhenzhao
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作者 HUANG Kai-hong NIE Zhen-zhao HE Qiong(Translator) 《Journal of Literature and Art Studies》 2024年第3期207-214,共8页
In 2014,Huang Kaihong,a professor at School of Foreign Languages and Cultures,Southwest University of Science and Technology,interviewed the Doctoral advisor Professor Nie Zhenzhao during the period of his academic vi... In 2014,Huang Kaihong,a professor at School of Foreign Languages and Cultures,Southwest University of Science and Technology,interviewed the Doctoral advisor Professor Nie Zhenzhao during the period of his academic visiting to Central China Normal University.As early as in 2005,Huang Kaihong conducted an interview with Professor Nie Zhenzhao on the topic of the general introduction of ethical literary criticism.So around 11 years later,the second interview mainly covers not only the ethical literary criticism theory,but the game theory and the relationship between them as well.Professor Nie thinks whether the game theory can be applied to literature research is still under discussion.The theory of ethical literary criticism is a kind of methodology based on science and it can get the attention of literary critics at home and abroad,which is because it fits the practical needs of literary criticism,draws the literary criticism away from only emphasizing criticism genres and the research of criticism terms,and pays attention to the true nature of the literary text in literature research.After consulting Professor Nie Zhenzhao about some related questions from the perspective of game theory.Huang Kaihong gets some significant information concerning literature research and understands the latest core terms and the concrete application method of ethical literary criticism,especially the relationship between the instructing and aesthetic functions of literature. 展开更多
关键词 ethical literary criticism game theory relationship methodology application
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Application of PCA and HCA to the Structure-Activity Relationship Study of Fluoroquinolones 被引量:2
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作者 李小红 张现周 +2 位作者 程新路 杨向东 朱遵略 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期143-148,共6页
Density functional theory (DFT) was used to calculate molecular descriptors (properties) for 12 fluoro-quinolone with anti-S.pneumoniae activity. Principal component analysis (PCA) and hierarchical cluster analy... Density functional theory (DFT) was used to calculate molecular descriptors (properties) for 12 fluoro-quinolone with anti-S.pneumoniae activity. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed to reduce dimensionality and investigate in which variables should be more effective for classifying fluoroquinolones according to their degree of an-S.pneumoniae activity. The PCA results showed that the variables ELUMO, Q3, Q5, QA, logP, MR, VOL and △EHL of these compounds were responsible for the anti-S.pneumoniae activity. The HCA results were similar to those obtained with PCA.The methodologies of PCA and HCA provide a reliable rule for classifying new fluoroquinolones with antiS.pneumoniae activity. By using the chemometric results, 6 synthetic compounds were analyzed through the PCA and HCA and two of them are proposed as active molecules with anti-S.pneumoniae, which is consistent with the results of clinic experiments. 展开更多
关键词 Structure-activity relationship Density functional theory Principal component analysis Hierarchical cluster analysis
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Linear QSAR Regression Models for the Prediction of Bioconcentration Factors of Chloroanilines in Fish by Density Functional Theory 被引量:16
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作者 冯长君 杨伟华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第6期830-834,共5页
Density functional theory(DFT)-B3LYP level with the 6-311G**(d,p) basis set was used to calculate a set of molecular quantum chemical descriptors of 12 chloroanilines. Quantitative structure-activity relationshi... Density functional theory(DFT)-B3LYP level with the 6-311G**(d,p) basis set was used to calculate a set of molecular quantum chemical descriptors of 12 chloroanilines. Quantitative structure-activity relationship(QSAR) models of the bioconcentration factors(BCF) of the anilines in fish were established using some of the following calculated descriptors: EHOMO, ENHOMO, ELUMO, ENLUMO, ΔE1(= ELUMO- EHOMO), ΔE2(= ENLUMO- ENHOMO), dipole moment(μ), molecular volume(V), vibrational energy of 0 K(Ev), thermodynamic energy(E), heat capacity(Cv), entropy(Sm) and the charge of benzene ring(Qph). Using the variable selection and leaps-and-bounds regression, the quantum chemical descriptors derived directly from the molecular structures were employed to develop a linear QSAR model between the bioconcentration factors(BCF) and two descriptors(Sm, ENHOMO) of 12 chloroanilines. Statistically, the most significant one is a two-parameter linear equation with the correlation coefficient(R^2) of 0.981 and cross-validated correlation coefficient(Rcv^2) of 0.967. The established QSAR model has good stability and predictability based on the results from Rcv2 of leave-one-out cross-validation, AIC, FIT and tα/2. The quantum chemical analyses were performed from two aspects of frontier molecular orbital and entropy. The results show that two structural describers are crucial to the bioconcentration activity of chloroanilines. 展开更多
关键词 CHLOROANILINES bioconcentration factor density functional theory quantum chemical describers quantitative structure-activity relationship
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Stress-Strain Relationship and Failure Criterion for Concrete after Freezing and Thawing Cycles 被引量:5
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作者 罗昕 卫军 《Journal of Southwest Jiaotong University(English Edition)》 2006年第3期265-271,共7页
The research of the failure criterion and one-dimensional stress-strain relationship of deteriorated concrete were carried out. Based on the damage mechanics theory, the dsmage which reflects the alternation of intern... The research of the failure criterion and one-dimensional stress-strain relationship of deteriorated concrete were carried out. Based on the damage mechanics theory, the dsmage which reflects the alternation of internal state of material were introduced into the formula presented by Desayi and Krishman and the weighted twin-shear strength theory. As a nondestructive examination method in common use, the ultrasonic technique was adopted in the study, and the ultrasonic velocity was used to establish the damage variable. After that, the failure criterion and one-dimensional stress-strain relationship for deteriorated concrete were obtained. Eventually, tests were carried out to study the evolution laws on the damage. The results show that the more freezing and thawing cycles are, the more apparently the failure surface shrinks. Meanwhile, the comparison between theoretical data and experimental data verifies tile rationality of tile damage-based one-dimensional stress-strain relationship proposed. 展开更多
关键词 CONCRETE DAMAGE Stress-strain relationship Strength theory Freezing and thawing cycles Supersonic velocity
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Studies of n-Octanol/water Partition Coefficients (lgK_(ow)) for Organophosphate Compounds by Density Functional Theory 被引量:2
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作者 LIU Hong-Xia WANG Zun-Yao +2 位作者 ZHAI Zhi-Cai LIU Hong-Yan WANG Lian-Sheng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第3期367-373,共7页
Optimized calculation of 35 dialkyl phenyl phosphate compounds (OPs) was carded out at the B3LYP/6-31G^* level in Gaussian 98 program. Based on the theoretical linear solvation energy relationship (TLSER) model, ... Optimized calculation of 35 dialkyl phenyl phosphate compounds (OPs) was carded out at the B3LYP/6-31G^* level in Gaussian 98 program. Based on the theoretical linear solvation energy relationship (TLSER) model, the obtained parameters were taken as theoretical descriptors to establish the novel QSPR model for predicting n-octanol/water partition coefficients (lgKow) of OPs. The new model achieved in this work contains three variables, i.e., molecular volume (Vm), dipole moment of the molecules (μ) and enthalpy (H^0). For this model, R^2 = 0.9167 and SD = 0.31 at large t values. In addition, the variation inflation factors (VIF) of variables are all close to 1.0, suggesting high accuracy of the predicting model. And the results of cross-validation test (q^2 = 0.8993) and method validation also showed the model of this study exhibited optimum stability and better predictive power than that from semi-empirical method. The model achieved can be used to predict IgKow of congeneric compounds. 展开更多
关键词 organophosphate compounds (OPs) n-octanol/water partition coefficients (Kow) quantitative structure-property relationship (QSPR) density functional theory (DFT)
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A novel binary effective medium model to describe the prepeak stressstrain relationship of combined bodies of rock-like material and rock 被引量:2
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作者 Tienan Wang Yue Zhai +2 位作者 Huan Gao Yubai Li Ruifeng Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第5期601-616,共16页
Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body ... Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body lack a binary feature.Based on effective medium theory,this paper presents the governing equation of the“elastic modulus”for combined and single bodies under triaxial compressive tests.A binary effective medium model is then established.Based on the compressive experiment of concretegranite combined bodies,the feasibility of determining the stress threshold based on crack axial strain is discussed,and the model is verified.The model is further extended to coal-rock combined bodies of more diverse types,and the variation laws of the compressive mechanical parameters are then discussed.The results show that the fitting accuracy of the model with the experimental curves of the concretegranite combined bodies and various types of coal-rock combined bodies are over 95%.The crack axial strain method can replace the crack volumetric strain method,which clarifies the physical meanings of the model parameters.The variation laws of matrix parameters and crack parameters are discussed in depth and are expected to be more widely used in geotechnical engineering. 展开更多
关键词 Combined body stress-strain relationship Hooke’s law Effective medium theory Stress threshold determination
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Dark Matter and the Energy-Momentum Relationship in a Hydrogen Atom 被引量:1
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作者 Koshun Suto 《Journal of High Energy Physics, Gravitation and Cosmology》 2020年第1期52-61,共10页
Einstein derived the energy-momentum relationship which holds in an isolated system in free space. However, this relationship is not applicable in the space inside a hydrogen atom where there is potential energy. Ther... Einstein derived the energy-momentum relationship which holds in an isolated system in free space. However, this relationship is not applicable in the space inside a hydrogen atom where there is potential energy. Therefore, in 2011, the author derived an energy-momentum relationship applicable to the electron constituting a hydrogen atom. This paper derives that relationship in a simpler way using another method. From this relationship, it is possible to derive the formula for the energy levels of a hydrogen atom. The energy values obtained from this formula almost match the theoretical values of Bohr. However, the relationship derived by the author includes a state that cannot be predicted with Bohr’s theory. In the hydrogen atom, there is an energy level with n = 0. Also, there are energy levels where the relativistic energy of the electron becomes negative. An electron with this negative energy (mass) exists near the atomic nucleus (proton). The name “dark hydrogen atom” is given to matter formed from one electron with this negative mass and one proton with positive mass. Dark hydrogen atoms, dark hydrogen molecules, other types of dark atoms, and aggregates made up of dark molecules are plausible candidates for dark matter, the mysterious type of matter whose true nature is currently unknown. 展开更多
关键词 Einstein’s ENERGY-MOMENTUM relationship Classical Quantum theory Ultra-Low Energy Levels DIRAC Relativistic Wave Equation DARK Matter DARK Hydrogen TRIPLET Production
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Network Biological Modeling:A Novel Approach to Interpret the Traditional Chinese Medicine Theory of Exterior-Interior Correlation Between the Lung and Large Intestine 被引量:2
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作者 CHEN Wen-Lu HONG Jia-Na +5 位作者 ZHANG Xin-Ning EMMANUEL Ibarra-Estrada WAN Li-Sheng LI Sha-Sha YAN Shi-Kai XIAO Xue 《Digital Chinese Medicine》 2020年第4期249-259,共11页
Objective To study the common pathogenesis of pneumonia and colitis using modern biological network analysis tools,and to explore the theory that the lung and large intestine are exteriorly and interiorly related.Meth... Objective To study the common pathogenesis of pneumonia and colitis using modern biological network analysis tools,and to explore the theory that the lung and large intestine are exteriorly and interiorly related.Methods The relevant target genes(hereinafter,“targets”)of pneumonia and colitis were separately queried on the GeneCards database.The main targets of the two diseases were then screened out according to their correlation scores and intersected to obtain those common to the two diseases.Metascape was used to analyze the main and common targets identified,and the Database for Annotation,Visualization and Integrated Discovery(DAVID)was used to enrich and analyze the common targets.Cytoscape 3.7.2 software was used to build the network diagram.Results In total,54 targets,such as TNF,IL-10,IL-6,IL-2,IL-4,TLR4,TLR2,CXCL8,IL-17A and IFNG,etc.,are common to pneumonia and colitis,which are mainly enriched in these processes such as cytokine–cytokine receptor interaction,the Tcell receptor signaling pathway,the Toll-like receptor signaling pathway and the Jak-STAT signaling pathway.The Metascape modular analysis identified 11 modules for pneumonia,six modules for colitis,and two modules for the common targets.Conclusions Pneumonia and colitis have the same pathogenic targets and mechanisms of action and finally interact with each other through inflammatory reactions and immune responses.This provides a probable molecular mechanism that explains the theory that the lung and large intestine are exteriorly and interiorly related. 展开更多
关键词 theory of the exterior-interior relationship between the lung and large intestine PNEUMONIA COLITIS Network pharmacology Th17 cell differentiation Inflammatory reactions Immune responses
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The Relationship between Comparative Linguistics and Translation
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作者 袁雷 《海外英语》 2017年第1期153-155,共3页
All theoires and rules for translation from Chinese into foreign languages or from foreign languages into Chinese are closely related to compartive linguistics. But, the relationship of the two can not be generalized ... All theoires and rules for translation from Chinese into foreign languages or from foreign languages into Chinese are closely related to compartive linguistics. But, the relationship of the two can not be generalized in the simple relation of theory and practice, for both of them there are theoretical and practical contents, the development of themselves plays a positive promoting role on the development of each other. Contrastive linguistics also exerting various influences on practice of translation.Contrastive linguistics and translation have a very close relationship, to apply the theory of comparative linguistics to translation studies will undoubtedly have to play a guiding role in the practice of translation, translation involves at least two languages, so it inevitably involve communication and transformation of two different cultures. This paper discusses the relationship between them from the perspective of vocabulary, grammar and discourse pragmatics to better direct the translation. 展开更多
关键词 Contrastive Linguistics TRANSLATION relationship theory PRACTICE
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1, 4-Pyrone Effects on O-H Bond Dissociation Energies of Catechols in Flavonoids: A Density Functional Theory Study
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作者 HongYuZHANG YouMinSUN 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第6期531-534,共4页
关键词 ANTIOXIDANT density functional theory flavonoid O-H bond dissociation energy structure-activity relationships.
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Quantitative Structure-activity Relationship Models of Monomer Reactivity
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作者 YU Xin-Liang YI Xiang YANG Hui-Qiong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第11期1867-1873,共7页
The reactivity parameters,Q and e,in the Q-e scheme reflect the reactivities of a monomer(or a radical)in free-radical copolymerizations.By applying multiple linear regression(MLR)analysis,the optimal quantitative str... The reactivity parameters,Q and e,in the Q-e scheme reflect the reactivities of a monomer(or a radical)in free-radical copolymerizations.By applying multiple linear regression(MLR)analysis,the optimal quantitative structure-activity relationship(QSAR)model for the reactivity parameter lnQ was developed based on five descriptors(NAF,NOF,EαLUMO,EβHOMO,and EβLUMO)and 69 monomers with the root mean square(rms)error of 0.61.The optimal MLR model of the parameter e obtained from five descriptors(TOcl,NpN,NSO,EαHOMO and DH)and 68 monomers produced rms error of 0.42.Compared with previous models,the two optimal MLR models in this paper show satisfactory statistical characteristics.The feasibility of combining 2D descriptors obtained from the monomers and 3D descriptors calculated from the radical structures(formed from monomers+H )to predict parameters Q and e has been demonstrated. 展开更多
关键词 density FUNCTIONAL theory MOLECULAR DESCRIPTORS multiple linear regression QUANTUM chemical DESCRIPTORS QUANTITATIVE STRUCTURE-ACTIVITY relationship
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Quantitative Structure-retention Relationship Study of Volatile Components from Rosa Banksiae Ait
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作者 程利平 包晓净 王根礼 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第8期1201-1211,共11页
In the present study,(QSRR) study had been carried out for volatile components from Rosa banksiae Ait.based on various quantum-chemical and physicochemical descriptors derived by B3LYP method.To build QSRR models,a ... In the present study,(QSRR) study had been carried out for volatile components from Rosa banksiae Ait.based on various quantum-chemical and physicochemical descriptors derived by B3LYP method.To build QSRR models,a multiple linear regression (MLR) stepwise method was used.The generated models have good predictive ability and are of high statistical significance with good correlation coefficients (R2≥0.734) and p values far less than 0.05.Preliminary results indicated that the application of the models,especially the prediction of GC retention time and linear retention index of volatile components from Rosa banksiae Ait.,will be helpful.The models contribute also to the identification of important quantum-chemical and physicochemical descriptors responsible for the retention time and linear retention index.It was found that the shape attribute (ShpA) and logP value play a vital role in determining component’s GC retention time and linear retention index which increase with the lipophilicity of volatile components.The larger the shape attribute of analyte is,the larger the deformability is,the stronger the interaction between analyte and stationary phase is,and the longer the GC retention time is,the larger the linear retention index is.The importance of E HOMO,q+,and SEV is also embodied in models,but they are not dominant. 展开更多
关键词 Rosa banksiae Ait. quantitative structure-retention relationship (QSRR) retention time linear retention index density functional theory (DFT)
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Solubility study of hydrogen in direct coal liquefaction solvent based on quantitative structure–property relationships model
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作者 Xiao-Bin Zhang A.Rajendran +1 位作者 Xing-Bao Wang Wen-Ying Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第12期250-258,共9页
Direct coal liquefaction(DCL)is an important and effective method of converting coal into high-valueadded chemicals and fuel oil.In DCL,heating the direct coal liquefaction solvent(DCLS)from low to high temperature an... Direct coal liquefaction(DCL)is an important and effective method of converting coal into high-valueadded chemicals and fuel oil.In DCL,heating the direct coal liquefaction solvent(DCLS)from low to high temperature and pre-hydrogenation of the DCLS are critical steps.Therefore,studying the dissolution of hydrogen in DCLS under liquefaction conditions gains importance.However,it is difficult to precisely determine hydrogen solubility only by experiments,especially under the actual DCL conditions.To address this issue,we developed a prediction model of hydrogen solubility in a single solvent based on the machine-learning quantitative structure–property relationship(ML-QSPR)methods.The results showed that the squared correlation coefficient R^(2)=0.92 and root mean square error RMSE=0.095,indicating the model’s good statistical performance.The external validation of the model also reveals excellent accuracy and predictive ability.Molecular polarization(a)is the main factor affecting the dissolution of hydrogen in DCLS.The hydrogen solubility in acyclic alkanes increases with increasing carbon number.Whereas in polycyclic aromatics,it decreases with increasing ring number,and in hydrogenated aromatics,it increases with hydrogenation degree.This work provides a new reference for the selection and proportioning of DCLS,i.e.,a solvent with higher hydrogen solubility can be added to provide active hydrogen for the reaction and thus reduce the hydrogen pressure.Besides,it brings important insight into the theoretical significance and practical value of the DCL. 展开更多
关键词 Hydrogen solubility Liquefied solvents Predictive model Density generalized function theory Quantitative structure-property relationship
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Estimation of n-Octanol/water Partition Coeffi-cients(lgK_(ow)) and the Aqueous Solubility(-lg_(Sw)) of all PCDF Congeners by Density Functional Theory
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作者 YANG Guo-Ying YU Jing +1 位作者 WANG Zun-Yao LIU Hong-Xia 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第9期1134-1140,共7页
Optimized calculation of dibenzofuran (DF) and 135 polychlorinated dibenzofurans (PCDFs) was carried out at the B3LYP/6-31G* level in GAUSSIAN 98 program. Based on the theoretical linear solvation energy relation... Optimized calculation of dibenzofuran (DF) and 135 polychlorinated dibenzofurans (PCDFs) was carried out at the B3LYP/6-31G* level in GAUSSIAN 98 program. Based on the theoretical linear solvation energy relationship (TLSER) model, the obtained structural parameters were taken as theoretical descriptors to establish the novel quantitative structureproperty relationship (QSPR) model for predicting n-octanol/water partition coefficients (lgKow) of PCDFs. The new model of lgKow achieved in this work contains three variables: energy of the highest occupied molecular orbital (EHOMO), the most negative atomic partial charge (q^-) and average molecular polarizability (a), of which R^2= 0.9011 and SD = 0,17 with larger t values. In addition, the variation inflation factors (VIF) of variables in the present model are all less than 5.5, suggesting high accuracy of the lgKow model. And the results of cross-validation test (q^2 = 0.8688) and method validation also show this model exhibits optimum stability and better predictive power than semi-empirical method. At the same time, it is found that the aqueous solubility (-lgSw) has high relative correlation with constant volume molar heat capacity (Cv^0), of which R^2 = 0.9777 and SD = 0.22. Moreover, lgKow and -lgSw values of all PCDF congeners were predicted respectively. 展开更多
关键词 polychlorinated dibenzofurans (PCDFs) n-octanol/water partition coefficients (lgKow) aqueous solubility (-lgSw) quantitative structureproperty relationship (QSPR) density functional theory (DFT)
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