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Investigation and Research on the Ordinary University High Level Track and Field Sports Teams in Sichuan Province
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作者 Dawei Li Bin Wang 《Open Journal of Applied Sciences》 2012年第4期148-153,共6页
by using the method of literature, questionnaire and mathematical statistics and comparative analysis and ?research method of sichuan university high level survey of the Track and field team, sichuan university high l... by using the method of literature, questionnaire and mathematical statistics and comparative analysis and ?research method of sichuan university high level survey of the Track and field team, sichuan university high level Track and field team and the analysis of existing problems and research, in order to sichuan university of high level Track and field teams development to provide the reference. 展开更多
关键词 SICHUAN Ordinary UNIVERSITY The high leve TRACK and FIELD TEAM RESEARCH
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Corresponding Prime Number Distribution Equation 被引量:1
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作者 Dan Liu Chenglong Liu 《Journal of Applied Mathematics and Physics》 2023年第11期3354-3365,共12页
The conjecture of twin prime numbers is a mathematical problem. Proving the twin prime conjecture using traditional modern number theory is extremely profound and complex. We propose an elementary research method for ... The conjecture of twin prime numbers is a mathematical problem. Proving the twin prime conjecture using traditional modern number theory is extremely profound and complex. We propose an elementary research method for corresponding prime number, proved that the conjecture of twin prime numbers and obtain the corresponding prime distribution equation. According to the distribution rate of corresponding prime numbers, the distribution pattern of twin prime numbers was proved the distribution rate theorem. This is the distribution rate of prime numbers corresponding to composite numbers, which approaches the distribution rate of prime numbers corresponding to integers. Based on the corresponding prime distribution equation, obtain the twin prime inequality function. Then, the formula for calculating twin prime numbers was discussed. There is also the Hardy Littlewood conjecture. This provides a practical and feasible approach for studying the distribution of twin prime numbers. 展开更多
关键词 Prime Number Composite Number Twin Prime Numbers Corresponding Prime Distribution Equation Twin Prime Inequality Function
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A summary of Copepoda:synthesis,trends,and ecological impacts
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作者 Vinod VAKATI Juan Manuel FUENTES-REINÉS +2 位作者 Pengbin WANG Jun WANG Steven DODSWORTH 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期1050-1072,共23页
Copepoda are one of the most significant animal groups present in aquatic ecosystems.Ecologists,evolutionary biologists,and biotechnologists continue to test new methods to study the application of Copepoda as model o... Copepoda are one of the most significant animal groups present in aquatic ecosystems.Ecologists,evolutionary biologists,and biotechnologists continue to test new methods to study the application of Copepoda as model organisms in various fields of pure and applied science,from evolution and ecology to aquaculture as live feed,as biological control of mosquito larvae,as biological indicators of water and sediment quality,in environmental monitoring and as a source of protein in the food industry.This paper reviews the current progress and trends within copepod research from a number of different perspectives.We emphasize the importance of Copepoda and the necessity of strengthening research on various topics related to copepod biology,some of which are of great significance to local sustainable development. 展开更多
关键词 BIOINDICATORS AQUACULTURE POLLUTANTS EUTROPHICATION NUTRITION HALOTOLERANCE
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New Planck’s Law
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作者 Dan Liu Bill 《Journal of Applied Mathematics and Physics》 2023年第3期721-736,共16页
In quantum mechanics, there are two very famous formulas. One is the energy formula of the bose particle, called Planck’s law. The other is the wavelength formula, which is called the de Broy wavelength. According to... In quantum mechanics, there are two very famous formulas. One is the energy formula of the bose particle, called Planck’s law. The other is the wavelength formula, which is called the de Broy wavelength. According to Einstein’s mass-energy equation, we have studied Planck’s law and De Bloy’s wavelength, and generalized it to the De Bloy’s wavelength formula from low speed to light speed. Then, on this basis, the smallest particle is defined as mass quantum. The new wavelength formula is obtained from the mass quantum and converted into the frequency formula. The generalized Planck’s law is obtained. 展开更多
关键词 Quantum Mechanics Planck’s Law Einstein’s Mass and Energy Equation Debroy Wavelength Generalized Planck’s Law
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A Low-Cost Smart Office Design Framework Using Arduino
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作者 Ssemwogerere Rajab Nabagesera Veronica Kawalya +10 位作者 Melese Alemsra Tsehayu Logose Masitula Wamwoyo Faruk Rahman Shiddiqur Ekwaro Dominic Mbalyowere Pasis Maritah Nambobi Mutwalibi Sayo Nakeleh Turay Mugerwa Derrick Kasagga Usama Seguya Asad 《Advances in Internet of Things》 2023年第3期83-108,共26页
The main motive of our research work is security enhancement and light energy conservation. This paper describes a study investigating the potential of a controlled office solution by integrating the Internet of Thing... The main motive of our research work is security enhancement and light energy conservation. This paper describes a study investigating the potential of a controlled office solution by integrating the Internet of Things (IoT) with wireless sensor networks (WSNs). A prototype of a smart office is developed using a global system of mobile Bluetooth and Radio Frequency Identification (RFID) technology. The user can turn on and off the fan remotely at any time. This prototype focuses on security and provides human-friendly assistance when in or out of the Office by integrating a mobile application platform. The innovative automated smart Office is designed with intelligent Security doors, lights, alarms, temperature humidifiers, and bright Liquid Crystal Display (LCD) screens for viewing. Our study has opened up virtual possibilities for producing cheap innovative frameworks in this Generation of IoT and the fifth Generation (5G) technology. Therefore, when implemented, this innovation will ease and improve human quality of life. So, this paper aims to provide a low-cost, effective Internet of the things-based automated smart Office. 展开更多
关键词 Intelligent Office Automation System Wireless Sensor Networks Internet of Things ULTRASONIC Radio Frequency Identification ARDUINO
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Several teleportation schemes of an arbitrary unknown multi-particle state via different quantum channels 被引量:21
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作者 彭家寅 莫智文 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期160-167,共8页
We first provide four new schemes for two-party quantum teleportation of an arbitrary unknown multi-particle state by using three-, four-, and five-particle states as the quantum channel, respectively. The successful ... We first provide four new schemes for two-party quantum teleportation of an arbitrary unknown multi-particle state by using three-, four-, and five-particle states as the quantum channel, respectively. The successful probability and fidelity of the four schemes reach 1. In the first two schemes, the receiver can only apply one of the unitary transformations to reconstruct the original state, making it easier for these two schemes to be directly realized. In the third and fourth schemes, the sender can preform Bell-state measurements instead of multipartite entanglement measurements of the existing similar schemes, which makes real experiments more suitable. It is found that the last three schemes may become tripartite controlled teleportation schemes of teleporting an arbitrary multi-particle state after a simple modification. Finally, we present a new scheme for three-party sharing an arbitrary unknown multi-particle state. In this scheme, the sender first shares three three-particle GHZ states with two agents. After setting up the secure quantum channel, an arbitrary unknown multi-particle state can be perfectly teleported if the sender performs three Bell-state measurements, and either of two receivers operates an appropriate unitary transformation to obtain the original state with the help of other receiver's three single-particle measurements. The successful probability and fidelity of this scheme also reach 1. It is demonstrated that this scheme can be generalized easily to the case of sharing an arbitrary unknown multi-particle state among several agents. 展开更多
关键词 quantum information quantum teleportation quantum state sharing multi-particle state
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Hierarchical and probabilistic quantum state sharing via a non-maximally entangled |χ〉state 被引量:22
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作者 彭家寅 柏明强 莫智文 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第1期74-79,共6页
A scheme that probabilistically realizes hierarchical quantum state sharing of an arbitrary unknown qubit state with a four-qubit non-maximally entangled |χ state is presented in this paper. In the scheme, the sender... A scheme that probabilistically realizes hierarchical quantum state sharing of an arbitrary unknown qubit state with a four-qubit non-maximally entangled |χ state is presented in this paper. In the scheme, the sender Alice distributes a quantum secret with a Bell-state measurement and publishes her measurement outcomes via a classical channel to three agents who are divided into two grades. One agent is in the upper grade, while the other two agents are in the lower grade. Then by introducing an ancillary qubit, the agent of the upper grade only needs the assistance of any one of the other two agents for probabilistically obtaining the secret, while an agent of the lower grade needs the help of both the other two agents by using a controlled-NOT operation and a proper positive operator-valued measurement instead of the usual projective measurement. In other words, the agents of two different grades have different authorities to reconstruct Alice's secret in a probabilistic manner. The scheme can also be modified to implement the threshold-controlled teleportation. 展开更多
关键词 |χ〉 state hierarchical quantum state sharing asymmetetric distribution positive operator-valued measurement
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Structural Characterization and Octanol/water Partition Coefficients(LogP) Prediction for Oxygen-containing Organic Compounds 被引量:8
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作者 廖立敏 黄茜 雷光东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第8期1243-1250,共8页
New descriptors were constructed and structures of some oxygen-containing organic compounds were parameterized. The multiple linear regression(MLR) and partial least squares regression(PLS) methods were employed t... New descriptors were constructed and structures of some oxygen-containing organic compounds were parameterized. The multiple linear regression(MLR) and partial least squares regression(PLS) methods were employed to build two relationship models between the structures and octanol/water partition coefficients(LogP) of the compounds. The modeling correlation coefficients(R) were 0.976 and 0.922, and the "leave one out" cross validation correlation coefficients(R(CV)) were 0.973 and 0.909, respectively. The results showed that the structural descriptors could well characterize the molecular structures of the compounds; the stability and predictive power of the models were good. 展开更多
关键词 oxygen-containing organic compounds octanol/water partition coefficients(LogP) structural descriptors relationship between structures and properties
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QSRR Study on the Components of Styrax Japonicus Sieb Flowers Using Improved Molecular Electronegativity-distance Vector (I-MEDV) 被引量:9
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作者 廖立敏 朱俊 +1 位作者 李建凤 雷光东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第1期105-110,共6页
Atoms in most organic molecules are often carbon,oxygen,nitrogen,sulfur,halogens,etc. Based on the three-dimensional structure of a molecule,a molecular structural characterization(MSC) method called improved molecu... Atoms in most organic molecules are often carbon,oxygen,nitrogen,sulfur,halogens,etc. Based on the three-dimensional structure of a molecule,a molecular structural characterization(MSC) method called improved molecular electronegativity-distance vector(I-MEDV) was developed. It was used to describe the structures of 37 compounds of styrax japonicus sieb flowers. Through multiple linear regression(MLR),a QSRR model was built up. The correlation coefficient(R1) of the model was 0.980. Then,4 vectors were selected to build another model through the method of stepwise multiple regression(SMR) ,and the correlation coefficient(R2) of the model was 0.975. Moreover,all the two models were evaluated by performing the crossvalidation with the leave-one-out(LOO) procedure and the correlation coefficients(Rcv) were 0.948 and 0.968,respectively. The results show that the I-MEDV could successfully describe the structures of organic compounds. The stability and predictability of the models were good. 展开更多
关键词 improved molecular electronegativity-distance vector(I-MEDV) structural descriptor quantitative structure-retention relationship(QSRR) flowers of styrax japonicus sieb complex samples
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The Clock gene clone and its circadian rhythms in Pelteobagrus vachelli 被引量:4
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作者 覃川杰 邵婷 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第3期597-603,共7页
The Clock gene,a key molecule in circadian systems,is widely distributed in the animal kingdom. We isolated a 936-bp partial c DNA sequence of the C lock gene( Pva- clock) from the darkbarbel catfish P elteobagrus vac... The Clock gene,a key molecule in circadian systems,is widely distributed in the animal kingdom. We isolated a 936-bp partial c DNA sequence of the C lock gene( Pva- clock) from the darkbarbel catfish P elteobagrus vachelli that exhibited high identity with C lock genes of other species of fish and animals(65%–88%). The putative domains included a basic helix-loop-helix(b HLH) domain and two period-ARNT-single-minded(PAS) domains,which were also similar to those in other species of fish and animals. P va- Clock was primarily expressed in the brain,and was detected in all of the peripheral tissues sampled. Additionally,the pattern of P va- Clock expression over a 24-h period exhibited a circadian rhythm in the brain,liver and intestine,with the acrophase at zeitgeber time 21:35,23:00,and 23:23,respectively. Our results provide insight into the function of the molecular C lock of P. vachelli. 展开更多
关键词 Clock gene Pelteobagrus vachelli circadian rhythms circadian gene
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Structural Characterization and Acute Toxicity Prediction of Substituted Aromatic Compounds by Using Molecular Vertexes Correlative Index 被引量:6
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作者 李建凤 廖立敏 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第4期557-563,共7页
A molecular structural characterization (MSC) method called molecular vertexes correlative index (MVCI) was used to describe the structures of 30 substituted aromatic compounds. Through multiple linear regression ... A molecular structural characterization (MSC) method called molecular vertexes correlative index (MVCI) was used to describe the structures of 30 substituted aromatic compounds. Through multiple linear regression (MLR) and stepwise multiple regression (SMR), a quantitative structure-toxicity relationship (QSTR) model with 4 variables was obtained. The correlation coefficient (R) of the model was 0.9467. Through partial least-squares regression (PLS), another QSTR model with 5 principal components was obtained. The correlation coefficient (R) of the model was 0.9518. Both models were evaluated by performing the cross-validation with the leave-one-out (LOO) procedure and the Cross-Validation (CV) correlation coefficients (Rcv) were 0.9208 and 0.9214, respectively. The results suggested good stability and predictability of the models, and the molecular vertexes correlative index could successfully describe the structures of the substituted aromatic compounds. 展开更多
关键词 substituted aromatics acute toxicity structural descriptors QSAR
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Structural Characterization and Retention Time Prediction for Components of Essential Oil of Meconopsis Integrifolia Flowers 被引量:5
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作者 廖立敏 李建凤 +1 位作者 卿东红 雷光东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第11期1638-1645,共8页
A molecular structural characterization (MSC) method called reduced molecular electronegativity-distance vector (MEDVR) was used to describe the molecular structures of 55 components of meconopsis integrifolia flo... A molecular structural characterization (MSC) method called reduced molecular electronegativity-distance vector (MEDVR) was used to describe the molecular structures of 55 components of meconopsis integrifolia flowers. By use of stepwise multiple regression (SMR) and partial least square (PLS) methods, a model with the correlation coefficient (R1) of 0.987 and the standard deviation (SD1) of 1.377 could be obtained. Then through multiple linear regression (MLR), another model with the correlation coefficient (R2) of 0.989 and standard deviation (SD2) of 1.395 could be constructed. Furthermore, in virtue of variable screening by the stepwise multiple regression technique (SMR), 8 vectors were selected to build up another model with its correlation coefficient (R3) and standard deviation (SD3) of 0.989 and 1.366, respectively. Then all the three models were evaluated by performing cross-validation with the leave-one-out (LOO) procedure, and the correlation coefficients (QCV) were 0.981, 0.976 and 0.979, respectively. The results show that the models constructed could provide estimation stability and favorable predictive ability. 展开更多
关键词 meconopsis integrifolia flowers reduced molecular electronegativity-distance vector (MEDVR) DESCRIPTOR quantitative structure-retention relationship
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Study on the Quantitative Structure-toxicity Relationships for the Selected Esters by Using Molecular Electronegativity Interaction Vector (MEIV) 被引量:4
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作者 李建凤 廖立敏 王碧 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第9期1225-1232,共8页
The molecular electronegativity interaction vector (MEIV) was used to describe the molecular structure of 30 selected esters. Two excellent QSTR models were built up by using multiple linear regression (MLR) and p... The molecular electronegativity interaction vector (MEIV) was used to describe the molecular structure of 30 selected esters. Two excellent QSTR models were built up by using multiple linear regression (MLR) and partial least-squares regression (PLS). The correlation coefficients (R) of the two models were 0.945 and 0.941, respectively. The models were evaluated by performing the cross validation with the leave-one-out (LOO) procedure. The cross-verification correlation coefficients (RCV) of the two models were 0.921 and 0.919, respectively. The results showed that the models constructed in this work could provide estimation stability and favorable predictive ability. 展开更多
关键词 ESTERS tetrahymena pyriformis half-inhibitory growth concentration (IGC50) structural characterization quantitative structure toxicity relationship (QSTR)
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Effects of solidification rate and excessive Fe on phase formation and magnetoclaoric properties of LaFe_(11.6x)Si_(1.4) 被引量:3
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作者 Xiang CHEN Yun-gui CHEN +1 位作者 Yong-bai TANG Ding-quan XIAO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第9期2015-2021,共7页
The effects of solidification rate and excessive Fe on phase formation and magnetocaloric properties of LaFe11.6xSi1.4(x=1.1,1.2)were investigated by XRD,SEM and VSM measurements.The XRD results show that the amount o... The effects of solidification rate and excessive Fe on phase formation and magnetocaloric properties of LaFe11.6xSi1.4(x=1.1,1.2)were investigated by XRD,SEM and VSM measurements.The XRD results show that the amount of LaFeSi phase in the as-cast melt-spun ribbons prepared by a copper wheel at a speed of10m/s is less than that in the as-cast arc melting buttons with the same x values.The annealed melt-spun ribbons contain smaller amount of La(Fe,Si)13(1:13)phase than the corresponding annealed arc melting buttons.Although the melt-spun sample has finer crystalline grains ofα-Fe,as indicated by SEM analysis,its crystalline size has not reached nano-scale.Therefore,the magnetic exchange-coupling between1:13phase andα-Fe phase has not been observed in melt-spun ribbons.Further,the maximum negative magnetic entropy change(?SMax)and relative cooling power(RCP)of annealed melt-spun ribbons under a field change of0?2T are weaker than those of the corresponding annealed arc melting buttons. 展开更多
关键词 LaFe11.6xSi1.4 alloy solidification rate MICROSTRUCTURE magnetocaloric properties
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Diurnal expression of circadian clock genes period 1 and period 3 in Pelteobagrus vachellii 被引量:2
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作者 Chuanjie QIN Ting SHAO +3 位作者 Xufeng LIAO Yang HE Jun WANG Peng HU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第2期652-660,共9页
Circadian clock genes are crucial for generating and sustaining most rhythmic daily functions in the animal kingdom,which entrain the rhythms of biochemical,physiological,and behavioural processes.To better understand... Circadian clock genes are crucial for generating and sustaining most rhythmic daily functions in the animal kingdom,which entrain the rhythms of biochemical,physiological,and behavioural processes.To better understand the molecular oscillations of the circadian rhythms in darkbarbel catfish(Pelteobagrus vachellii),we isolated and characterized two circadian clock genes in P.vachellii,period 1(per1),and period 3(per3).The circadian clock gene per1 was found to encode a 1428-amino acid polypeptide,including PER-ARNT-SIM(PAS)dimerisation domains,a PAS-associated C-terminal motif(PAC),a short mutable domain(S/M),and a nuclear export signal(NES).The 4902-bp per3 cDNA includes an open reading frame encoding a 1292-amino acid residue polypeptide with a PER-ARNT-SIM(PAS)domain,cytoplasmic localisation domain(CLD),interaction site(TIS),and a nuclear localisation signal(NLS).The per1 and per3 gene was constitutively expressed in all examined tissues.Moreover,per1 expression within a light/dark cycles showed rhythmic expression in the diencephalon,brain,liver and intestine,with the acrophase at 15:15,12:52,7:51 and 12:55,respectively.Daily expression of per3 was rhythmic in the diencephalonbrain,liver and intestine,with the acrophase at 8:15,9:54,10:39,and 10:25 h,respectively.These findings expand our understanding of circadian mechanism at the molecular level in this species. 展开更多
关键词 CDNA circadian rhythm diurnal expression Pelteobagrus vachellii period 1 period 3
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Boundedness of Linear Commutators on Herz-Morrey Spaces on Spaces of Homogeneous Type 被引量:3
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作者 GAO Wen-hua JIANG Yin-sheng GONG Xiao-bing 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第2期172-181,共10页
Under certain weak local size conditions, the boundedness of linear commutators on Herz-Morrey spaces on spaces of homogeneous type are studied. In addition, the boundedness of Hardy-Littlewood maximum commutators on ... Under certain weak local size conditions, the boundedness of linear commutators on Herz-Morrey spaces on spaces of homogeneous type are studied. In addition, the boundedness of Hardy-Littlewood maximum commutators on Herz-Morrey spaces on spaces of homogeneous type are obtained. 展开更多
关键词 homogeneous spaces Herz spaces COMMUTATORS Hardy-Littlewood maximum function
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First-principles calculation of the lattice compressibility,elastic anisotropy and thermodynamic stability of V_2GeC 被引量:2
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作者 杨则金 郭云东 +1 位作者 令狐荣锋 杨向东 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第3期328-334,共7页
We investigate the elastic and the thermodynamic properties of nanolaminate V2GeC by using the ab initio pseudopotential total energy method. The axial compressibility shows that the c axis is always stiffer than the ... We investigate the elastic and the thermodynamic properties of nanolaminate V2GeC by using the ab initio pseudopotential total energy method. The axial compressibility shows that the c axis is always stiffer than the a axis. The elastic constant calculations demonstrate that the structural stability is within 0-800 GPa. The calculations of Young's and shear moduli reveal the softening behaviour at about 300 GPa. The Possion ratio makes a higher ionic or a weaker covalent contribution to intra-atomic bonding and the degree of ionicity increases with pressure. The relationship between brittleness and ductility shows that V2GeC is brittle in ambient conditions and the brittleness decreases and ductility increases with pressure. Moveover, we find that V2CeC is largely isotropic in compression and in shear, and the degree of isotropy decreases with pressure. The Griineisen parameter, the Debye temperature and the thermal expansion coefficient are also successfully obtained for the first time. 展开更多
关键词 V2GeC first principles ELASTICITY thermodynamic properties
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Structural Characterization and Acute Toxicity Simulation for Nitroaromatic Compounds 被引量:10
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作者 廖立敏 黄茜 李建凤 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第3期449-456,共8页
The three-dimensional holographic vector of atomic interaction field(3D-Ho VAIF) is used to characterize the molecular structures of 45 nitroaromatic compounds.Two quantitative structure-toxicity relationship(QSAR... The three-dimensional holographic vector of atomic interaction field(3D-Ho VAIF) is used to characterize the molecular structures of 45 nitroaromatic compounds.Two quantitative structure-toxicity relationship(QSAR) models are built up by stepwise regression(SMR),multiple linear regression(MLR) and partial least-squares regression(PLS).The correlation coefficients(R) of the models are 0.960 and 0.961,respectively.Then the models are evaluated by performing the cross-validation with the leave-one-out(LOO) procedure and the correlation coefficients(RCV) are 0.949 and 0.941,respectively.The results show that the descriptors can successfully describe the structures of organic compounds.The stability and predictability of the model are satisfactory. 展开更多
关键词 nitroaromatic compounds structural descriptor toxicity QSAR
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Location-allocation modeling for emergency evacuation planning with GIS and remote sensing:A case study of Northeast Bangladesh 被引量:7
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作者 Mahfuzur Rahman Ningsheng Chen +8 位作者 MdMonirul Islam Ashraf Dewan Hamid Reza Pourghasemi Rana Muhammad AliWashakh Nirdesh Nepal Shufeng Tian Hamid Faiz Mehtab Alam Naveed Ahmed 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第3期169-185,共17页
This work developed models to identify optimal spatial distribution of emergency evacuation centers(EECs)such as schools,colleges,hospitals,and fire stations to improve flood emergency planning in the Sylhet region of... This work developed models to identify optimal spatial distribution of emergency evacuation centers(EECs)such as schools,colleges,hospitals,and fire stations to improve flood emergency planning in the Sylhet region of northeastern Bangladesh.The use of location-allocation models(LAMs)for evacuation in regard to flood victims is essential to minimize disaster risk.In the first step,flood susceptibility maps were developed using machine learning models(MLMs),including:Levenberg-Marquardt back propagation(LM-BP)neural network and decision trees(DT)and multi-criteria decision making(MCDM)method.Performance of the MLMs and MCDM techniques were assessed considering the area under the receiver operating characteristic(AUROC)curve.Mathematical approaches in a geographic information system(GIS)for four well-known LAM problems affecting emergency rescue time are proposed:maximal covering location problem(MCLP),the maximize attendance(MA),p-median problem(PMP),and the location set covering problem(LSCP).The results showed that existing EECs were not optimally distributed,and that some areas were not adequately served by EECs(i.e.,not all demand points could be reached within a 60-min travel time).We concluded that the proposed models can be used to improve planning of the distribution of EECs,and that application of the models could contribute to reducing human casualties,property losses,and improve emergency operation. 展开更多
关键词 Natural disasters Emergency evacuation centers FLOODING Machine learning Multi-criteria decision making Location-allocation model
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Soil Aggregates and Fractal Features under Different Land Use Types in a Frequent Debris Flow Area 被引量:1
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作者 XIE Xian-jian WEI Fang-qiang 《Journal of Mountain Science》 SCIE CSCD 2013年第3期437-444,共8页
The stability of soil aggregates and the fractal characteristics of four typical land use types(farmland,grassland,woodland,and bare land) in the Jiangjiagou Ravine(Yunnan,China),a frequent debris flow occurring area,... The stability of soil aggregates and the fractal characteristics of four typical land use types(farmland,grassland,woodland,and bare land) in the Jiangjiagou Ravine(Yunnan,China),a frequent debris flow occurring area,were studied according to the normal mean mass diameter and fractal theory.The present research showed that the stability of the soil aggregates was different for the different land use types.When the soil depth was 0-30 cm,farmland soil formed more aggregates with diameters greater than 0.25 mm,i.e.,the farmland soil was more stable than that of the other three land uses.When the soil depth was 30-45 cm,the order of stability of the soil aggregates was woodland > grassland > farmland > bare land.The fractal dimensions had a significant linear positive correlation with the amount of soil particles with diameters of <0.25 mm,and a significant negative linear correlation with the amount of soil particles with diameters of 0.25-0.5 mm,0.5-1 mm and 1-2 mm.Smaller fractal dimensions of the soil particles correlated with more stable soil aggregates.The fractal dimensions had a positive linear correlation with the soil bulk density and a negative correlation with the concentration of organic matter.These results showed that soil aggregates can be used as a parameter for characterizing the soil structures and properties.According to these results,the soil particle fractal dimensions could not only objectively characterize the stability of the soil structure but also could be used to indicate soil structure and properties.In addition,these results have great significance for the discussion of the comprehensive evaluation of soil. 展开更多
关键词 Debris flow Land use pattern AGGREGATES Fractal dimension
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