Saturation Estimation with Complex Electrical Conductivity for Hydrate-Bearing Clayey Sediments:An Experimental Study

Clays have considerable influence on the electrical properties of hydrate-bearing sediments.It is desirable to understand the electrical properties of hydrate-bearing clayey sediments and to build hydrate saturation(S_(h))models for reservoir evaluation and monitoring.The electrical properties of tetrahydrofuran-hydrate-bearing sediments with montmorillonite are characterized by complex conductivity at frequencies from 0.01 Hz to 1 kHz.The effects of clay and Sh on the complex conductivity were analyzed.A decrease and increase in electrical conductance result from the clay-swelling-induced blockage and ion migration in the electrical double layer(EDL),respectively.The quadrature conductivity increases with the clay content up to 10%because of the increased surface site density of counterions in EDL.Both the in-phase conductivity and quadrature conductivity decrease consistently with increasing Sh from 0.50 to 0.90.Three sets of models for Sh evaluation were developed.The model based on the Simandoux equation outperforms Archie’s formula,with a root-mean-square error(E_(RMS))of 1.8%and 3.9%,respectively,highlighting the clay effects on the in-phase conductivity.The fre-quency effect correlations based on in-phase and quadrature conductivities exhibit inferior performance(E_(RMS)=11.6%and 13.2%,re-spectively)due to the challenge of choosing an appropriate pair of frequencies and intrinsic uncertainties from two measurements.The second-order Cole-Cole formula can be used to fit the complex-conductivity spectra.One pair of inverted Cole-Cole parameters,i.e.,characteristic time and chargeability,is employed to predict S_(h) with an E_(RMS) of 5.05%and 9.05%,respectively.

The c-axis complex permittivity and electrical impedance in BaFe_2As_2: Experimental examination on transformation validity

Complex permittivity and electrical impedance have been measured along the c-axis in single crystals BaFe_2 As_2,which are the conductors known as the parent compound of 122-type iron superconductor. The resultant relative errors defined in the study indicate the existence of the transformation between complex permittivity and electrical impedance in the conductors, and these two physics quantities possibly reveal different aspects of the consistent superconductivityrelevant physics picture.

Failure to fire after an electrical injury——A complex syndrome in a soldier: complex regional pain syndrome(CRPS)

Complex regional pain syndrome(CRPS) is a disorder characterized by an intractable, disabling pain of the affected limb. It is triggered by various injuries and is often resistant to standard therapy. We report a young soldier with CRPS of the right hand sustained from an electrical injury, who had improvement in resting pain with Zoledronic acid. In this report, we discuss the therapeutic options and the role of bisphosphonates in CRPS.

SYNTHESIS,CHARACTERIZATION,THERMAL DEGRADATION AND ELECTRICAL CONDUCTIVITY OF OLIGO[2-(THIEN-2-YLMETHYLENE)AMINOPHENOL]AND OLIGOMER-METAL COMPLEXES

The optimum reaction conditions of the oxidative polycondensation of 2-(thien-2-yl-methylene)aminophenol (2-TMAP) has been accomplished by using air O_2,H_2O_2 and NaOCl oxidants in an aqueous alkaline medium between 20℃and 90℃.The structures of the monomer and oligomer were confirmed by FT-IR,UV-Vis,~1H-NMR and ^(13)C-NMR and elemental analysis.TGA-DTA,size exclusion chromatography(SEC) techniques and solubility tests were applied for characterization.The ~1H-NMR and ^(13)C-NMR data show that the polymeriz...

ELECTRIC PROPERTY AND STRUCTURE OF EOSIN B,ROSE BENGAL,EOSIN 10B (PHLOXINE B) AND THEIR RARE EARTH COMPLEXES

The electric property and structure of some fluorescein derivatives and their rare earthcomplexes have been reported before.In order to investigate the effect of differentsubstituents on the electric property,the change of resistivity with temperature of eosin B(disodium salt of dibromodinitrofluorescein),rose bengal (disodium salt of tetrachlorotetraiodofluorescein),eosin 10B (dipotassium salt of dichlorotetrabromofluorescein) andtheir complexes with La(Ⅲ),Ce(Ⅲ),Gd(Ⅲ) and Y(Ⅲ) is studied in this paper.

Synthesis,Structure,and Surface Photo-electric Properties of a New Zn(Ⅱ)Coordination Complex Constructed from 2-(1H-benzotriazol-1-yl)acetic Acid and 1,10-Phenanthroline Ligands

A new binuclear Zn^Ⅱ coordination complex,Zn2（bta）（phen）2（Cl）3（1,Hbta = 2-（1Hbenzotriazol-1-yl）acetic acid and phen = 1,10-phenanthroline）,has been synthesized and characterized by single-crystal X-ray diffraction,IR spectroscopy,elemental,and photoluminescent analysis.Complex 1 crystallizes in triclinic system,space group P1 with a = 9.3040（19）,b = 10.694（2）,c =16.841（3） A°,α = 101.18（3）,β = 105.77（3）,γ = 91.72（3）°,V= 1575.8（5） A°3,C（32）H（22）Zn2Cl3N7O2,Mr =773.66,Dc = 1.631 g/cm^3,Z = 2,F（000） = 780,μ = 1.820 mm^-1,the final R = 0.1238 and wR =0.1131.X-ray diffraction analyses indicate that 1 displays two crystallographic independent Zn^Ⅱmetal centers with a distorted tetragonal pyramidal（ZnN4O） and a tetrahedral（ZnNCl3） geometries,respectively.The phen serves as a common N,N＇-bidentate ligand,and the bta^- as a unique N,O-bridged ligand in 1.In the crystal,1 forms a stable 3D supramolecular architecture by trifurcated hydrogen bonding C-H…C1 interactions and C-H…π,π…π stacking.1 showed photo-electric conversion properties.

Application of a Bayesian Network Complex System Model Examining the Importance of Customer-Industry Engagement to Peak Electricity Demand Reduction

This paper explores the importance of customer-industry engagement (CIE) to peak energy demand by means of a newly developed Bayesian Network (BN) complex systems model entitled the Residential Electricity Peak Demand Model (REPDM). The REPDM is based on a multi-disciplinary perspective designed to solve the complex problem of residential peak energy demand. The model provides a way to conceptualise and understand the factors that shift and reduce consumer demand in peak times. To gain insight into the importance of customer-industry engagement in affecting residential peak demand, this research investigates intervention impacts and major influences through testing five scenarios using different levels of customer-industry engagement activities. Scenario testing of the model outlines the dependencies between the customer-industry engagement interventions and the probabilities that are estimated to govern the dependencies that influence peak demand. The output from the model shows that there can be a strong interaction between the level of CIE activities and interventions. The influence of CIE activity can increase public and householder support for peak reduction and the model shows how the economic, technical and social interventions can achieve greater peak demand reductions when well-designed with appropriate levels of CIE activities.

Electrical properties of m×n cylindrical network

We consider the problem of electrical properties of an m×n cylindrical network with two arbitrary boundaries,which contains multiple topological network models such as the regular cylindrical network,cobweb network,globe network,and so on.We deduce three new and concise analytical formulae of potential and equivalent resistance for the complex network of cylinders by using the RT-V method(a recursion-transform method based on node potentials).To illustrate the multiplicity of the results we give a series of special cases.Interestingly,the results obtained from the resistance formulas of cobweb network and globe network obtained are different from the results of previous studies,which indicates that our research work creates new research ideas and techniques.As a byproduct of the study,a new mathematical identity is discovered in the comparative study.

The electrical switching characteristics of single copper tetra-cyanoquinodimethane nanowire

In this paper, method combined vapor transportation with in-situ chemical reaction is employed to synthesize Cu(TCNQ) nanowires. The typical diameter of nanowires is 50-500 nm with high uniformity. The electrical switching characteristics of single nanowire are observed. The ON-OFF resistance ratio for switching reaches 10~4. The investigation reveals a linear relationship between the switching threshold and the spacing between the two electrodes. The temporal response of the switching process is 30 ns and the switch exhibits good reproducibility. The collapse of the nanowire under the condition of current surge is also discussed. It is believed that the Cu(TCNQ) nanowire could be promising for applications in nanoelectronics.

Resonances of a hydrogen atom in strong parallel electric and magnetic fields using B-spline basis sets

The B-spline basis set plus complex scaling method is applied to the numerical calculation of the exact resonance parameters Er and Г/2 of a hydrogen atom in parallel electric and magnetic fields. The method can calculate the ground and higher excited resonances accurately and efficiently. The resonance parameters with accuracies of 10^-9 - 10^-12 for hydrogen atom in parallel fields with different field strengths and symmetries are presented and compared with previous ones. Extension to the calculation of Rydberg atom in crossed electric and magnetic fields and of atomic double excited states in external electric fields is discussed.

High-Frequency Electric Field Induced Nonlinear Electron Transport in Chiral Carbon Nanotubes

We investigate theoretically the high frequency complex conductivity in carbon nanotubes that are stimulated axially by a strong inhomogeneous electric field of the form E(t)=E0+E1cos(ωt). Using the kinetic approach based on Boltzmann’s transport equation with constant relaxation time approximation and the energy spectrum of the electron in the tight-binding approximation, together with Bhatnagar-Gross-Krook collision integral, we predict high-frequency nonlinear effects along the axial and the circumferential directions of the carbon nanotubes that may be useful for the generation of high frequency radiation in the carbon nanotubes.

Electrical Noise, Brownian Motion and the Arrow of Time

The origin of the Johnson noise of resistors is reviewed by a new model fitting in the Fluctuation-Dissipation framework and compared with the velocity noise in Brownian motion. This new model handling both fluctuations as well as dissipations of electrical energy in the Complex Admittance of any resistor excels current model based on the dissipation in their conductance. From the two orthogonal currents associated to a sinusoidal voltage in an electrical admittance, the new model that also considers the discreteness of the electrical charge shows a Cause-Effect dynamics for electrical noise. After a brief look at systems considered as energy-conserving and deterministic on the microscale that are dissipative and unpredictable on the macroscale, the arrow of time is discussed from the noise viewpoint.

Effect of Sintering Time on the Structural, Magnetic and Electrical Transport Properties of Mg_0.35Cu_0.20Zn_0.45Fe_1.94O₄Ferrites

Spinel-type Mg0.35Cu0.20Zn0.45Fe1.94O4 ferrites were synthesized by using the solid-state reaction technique. The XRD patterns of the sintered samples indicated the formation of single-phase cubic spinel structure. The apparent density of the sample is found to increase whereas porosity decreases with the increase in sintering time. The grain growth of the samples is enhanced with the increase in sintering time which is attributed to the liquid phase due to CuO during sintering. The initial permeability of the ferrite is found to increase with the increase in sintering time but the resonance frequency shifts towards the lower frequency. This increase in permeability is correlated to the increase of density and the grain size of the sample. The resistivity of the samples decreases with 103/T ensuring the semiconducting nature of the samples. Room temperature DC resistivity and activation energy of the samples decrease what is attributed to the increased Fe2+ ions content with the increase in sintering time. The dielectric constant (e￠) of the samples decreases with increasing frequency whereas e￠ increases as the temperature increases exhibiting normal dielectric behaviour of the magnetic semiconductor ferrite. The observed variation of electrical and dielectric properties is explained on the basis of Fe2+/Fe3+ ionic concentration as well as the electronic hopping frequency between Fe3+ and Fe2+ ions in the present ferrite sample.

High Electrical Conductivity and Conspicuous Phase Transitions in Single Crystals of K-TCNQ

This paper is to report the temperature dependent electrical conductivity of single crystals of radical ion salt (RIS) potassium-TCNQ (K-tetracyanoquino- dimethane) in a wide range of temperatures from 30 to 500 K. This RIS is quasi-one-dimensional in nature. These single crystals of K-TCNQ are grown by different methods like electrochemical, solution growth and diffusion method. Activation energy is determined for the sample in different temperature regions and found different values. More than one semiconductor to metal phase transition is observed in the studied samples during electrical measurements below and above room temperature. All the features observed in the studied samples are analyzed in the framework of their molecular structure as well as under different effects like disorder, impurity, Coulomb interaction, charge density wave (CDW), scattering and 3-D effects etc.

Hydrothermal Synthesis, Crystal Structure and Surface Photo-electric Properties of a New Nickel(Ⅱ) 3-D Metalorganic Framework Constructed from the Rigid 1,4-Bis(imidazol-1-yl) benzene Ligand

A new 3-D nickel（Ⅱ） metal-organic framework（MOFs） with formula [Ni（bib）_2（SO_4）]_n（1）, where bib = 1,4-bis（imidazol-1-yl）benzene, has been synthesized and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and surface photovoltage spectroscopy（SPS）. Complex 1 crystallizes in monoclinic system, space group C2/c with a = 19.5988（6）, b = 9.7531（3）, c = 11.8146（4） ？, β = 96.185（3）°, V = 2245.20（12） ？~3, C_（24）H_（20）N_8NiO_4S, M_r = 575.25, D_c = 1.702 g/cm^3, Z = 4, F（000） = 1184, μ = 1.011 mm-1, the final R = 0.0293 and w R = 0.0702. X-ray diffraction analyses indicated that the center Ni^（2＋） ion is six-coordinated with an O_2N_4 donor set of two μ_2-SO_4^（2–） and four bib ligands, resulting in an ideal octahedral geometry. Topological analysis on complex 1 considers each Ni^（2＋） as a 6-connected node, while bib and sulfate ion as linkers, giving an α-Po topology with short Schl？fli symbol 412·63. In the crystal packing, the components interact with pairs of intermolecular C–H×××O hydrogen bonds. The SPS of 1 indicates that there are positive response bands in the range of 300~600 nm showing photo-electric conversion properties.

千特斯拉级内爆磁压缩装置初始磁场电源系统研制

初始磁场电源系统用于激励千特斯拉级内爆磁压缩装置的初级线圈产生初始磁场,是内爆磁压缩装置的关键设备。在分析千特斯拉级内爆磁压缩装置初始磁场电源需求和技术难点的基础上,系统设计了核心部件选择方案和主脉冲电路及控制系统结构,研制成功一套输出电压1~40 kV可调、主放电电流脉冲上升沿约60μs、总峰值电流达3.2 MA的初始磁场电源系统,已应用于千特斯拉级内爆磁压缩装置动态试验。

智慧城市科学与工程新兴交叉学科建设的探索与思考

智慧城市科学与工程新兴交叉学科面向建筑智能化发展需求,以创新型人才培养为核心,探索解决复杂工程问题能力培养途径。采用多元化实践教学方式,通过优化课程与实践教学体系、强化教学团队建设、构建协同育人平台和实施立体化评价体系,逐步提高教师跨学科教学、科研能力,提升学生的工程实践能力、交叉融合意识、协作精神,促进学生全面发展。而该学科在建设过程中也面临诸多困难与挑战,通过深化交流合作、扩大师资队伍规模、提升学生交叉融合意识和注重评价体系反馈等措施,推动智慧城市科学与工程交叉学科建设的快速进展,为城市智慧化、绿色化提供人才保障。

某纯电驱动重载车辆能耗预测模型

高精度能耗预测模型是准确预测车辆续驶里程的重要前提。针对载荷大幅度变化且非结构化道路运行的纯电驱动重载车辆,建立其组合能耗模型,该模型由能耗计算基本模型与长短时记忆(Long Short-Term Memory,LSTM)神经网络差值修正两部分组成。基于能量流动过程驱动电机和变速器效率建模,结合汽车行驶动力学建立能耗计算基本模型;采用LSTM神经网络来修正基本模型能耗预测结果与车辆典型工况功率测试值的差值,有效提高了大幅变载荷且低信噪比坡度环境下的车辆能耗预测精度,因此组合能耗模型具有参数简单和模型拟合不需解释能耗规律的优点。经试验测试分析,与VT-Micro能耗模型和径向基(Radial Basis Function,RBF)神经网络能耗模型相比,所提组合能耗模型的功率预测平均误差率分别降低了17.76%和3.35%,能够实现纯电驱动重载车辆复杂工况下能耗的准确实时预测。

慢性心力衰竭患者心电图QRS波时限与心室电-机械不同步的关系

目前许多研究表明,QRS波时限与心室机械不同步并非完全呈线性关系,然而心室同步电激活是心室正常收缩舒张的重要先决条件。慢性心力衰竭(简称心衰)患者常常存在心室收缩功能障碍。尽管心衰初期心脏会发生适应性改变,但一旦超过代偿范围,就会导致心脏重构,使心功能严重受损。心电-机械重构受心脏结构、细胞水平和分子水平等因素的多重影响,在心电图上可以表现为QRS波时限增宽。在心衰的治疗方面,除了传统起搏器以外,近些年新兴的传导系统起搏更符合生理传导的特点,能在显著缩短QRS波时限的同时显著改善心室的机械同步性。本文综述了慢性心衰患者发生电-机械不同步的可能机制及其与QRS波时限的关系,以及二者对心功能的影响。