Derivation of energy-based base shear force coefficient considering hysteretic behavior and P-delta effects

A modified energy-balance equation accounting for P-delta effects and hysteretic behavior of reinforced concrete members is derived. Reduced hysteretic properties of structural components due to combined stiffness and strength degradation and pinching effects, and hysteretic damping are taken into account in a simple manner by utilizing plastic energy and seismic input energy modification factors. Having a pre-selected yield mechanism, energy balance of structure in inelastic range is considered. P-delta effects are included in derived equation by adding the external work of gravity loads to the work of equivalent inertia forces and equating the total external work to the modified plastic energy. Earthquake energy input to multi degree of freedom（MDOF） system is approximated by using the modal energy-decomposition. Energybased base shear coefficients are verified by means of both pushover analysis and nonlinear time history（NLTH） analysis of several RC frames having different number of stories. NLTH analyses of frames are performed by using the time histories of ten scaled ground motions compatible with elastic design acceleration spectrum and fulfilling duration/amplitude related requirements of Turkish Seismic Design Code. The observed correlation between energy-based base shear force coefficients and the average base shear force coefficients of NLTH analyses provides a reasonable confidence in estimation of nonlinear base shear force capacity of frames by using the derived equation.

Experimental Podophyllotoxin (Bajiaolian) Poisoning:Ⅲ. Biochemical Bases for Toxic Effects

The biochemical mechanism underlying the toxicity of podophyllotoxin is investigated.Previous studies from our laboratories suggested that hepatocytes were extremely sensitive to the toxicity of podophyllotoxin and a disruption of protein synthesis was suspected.Dose-response and time-course studies on the effects of podophyllotoxin on protein, RNA,and DNA syniheses on hepatocellular cultures were made. Inhibitions of protein, RNA,and DNA syntheses were demonstrated, and a direct correlated dose-response relationshipon such effects was also evident. Inhibition of protein synthesis appeared to be a direet toxic effect of podophyllotoxin and occurred independently from that of RNA. The reduction of DNA synthesis was reflected by a reduction of H3-thymidine incorporation,which is believed to be the consequence of inhibition on the mitotic activity by podophyllotoxin

Benchmark Dose Estimation for Cadmium-Induced Renal Effects Based on a Large Sample Population from Five Chinese Provinces

A survey involving 6103 participants from five Chinese provinces was conducted to evaluate the threshold value of urinary cadmium （UCd） for renal dysfunction as benchmark dose low （BMDL）. The urinary N-acetyl-13-D-glucosaminidase （UNAG） was chosen as an effect biomarker. The UCd BMDLs for UNAG ranged from 2.18μg/g creatinine （cr） to 4.26μg/g cr in the populations of different provinces. The selection of the sample population and area affect the evaluation of the BMDL. The reference level of UCd for renal effects was further evaluated based on the data of all 6103 subjects. With benchmark responses （BMR） of 10%/5%, the overall UCd BMDLs for males in the total population were 3.73/2.08 μg/g cr. The BMD was slightly lower in females, thereby indicating that females may be relatively more sensitive to Cd exposure than are males.

Electrocaloric effect in ferroelectric materials:From phase field to first-principles based effective Hamiltonian modeling

Electrocaloric effect(ECE)of ferroelectrics has attracted considerable interest due to its potential application in environmentally friendly solid-state refrigeration.The discovery of giant ECE in ferroelectric thin films has greatly renewed the research activities and significantly stimulated experimental and theoretical investigations.In this review,the recent progress on the theoretical modeling of ECE in ferroelectric and antiferroelectric materials are introduced,which mainly focuses on the phase field modeling and first-principles based effective Hamiltonian method.We firstly provide the theoretical foundation and technique details for each method.Then a comprehensive review on the progress in the application of two methods and the strategies to tune the ECE are presented.Finally,we outline the practical procedure on the development of multi-scale computational method without experiemtal parameters for the screening of optimized electrocaloric materials.

Tunable Band Gap in Piezoelectric Composite Rod Based on the Inter-Coupling Effect

The longitudinal wave propagating in one-dimensional periodic piezoelectric composite rod with inter-coupling between different piezoelectric segments is investigated. The analytical formulae for such a structure are shown and the dispersion relation is calculated. The results show that, by introducing the inter-coupling between the different piezoelectric segments, which is accomplished by serially connecting every n piezoelectric segment into supercells, some tunable Bragg band gaps can accordingly be opened in the low frequency region. The investigation could provide a new guideline for the tunable phononic crystal under passive control.

High-Temperature Performance Analysis of AlGaN/GaN Polarization Doped Field Effect Transistors Based on the Quasi-Multi-Channel Model

We report on the temperature-dependent dc performance of A1GaN/GaN polarization doped field effect transistors （PolFETs）. The rough decrements of drain current and transeonductance with the operation temperature are observed. Compared with the conventional HFETs, the drain current drop of the PolFET is smaller. The transeonductance drop of PolFETs at different gate biases shows different temperature dependences. From the aspect of the unique carrier behaviors of graded AlGaN/GaN heterostructure, we propose a quasi-multi-channel model to investigate the physics behind the temperature-dependent performance of AlGaN/GaN PolFETs.

Dick Effect in a Microwave Frequency Standard Based on Laser-Cooled 113Cd+ Ions

The Dick effect is one of the main limits to the frequency stability of a passive frequency standard, especially for the fountain clock and ion dock operated in pulsed mode which require unavoidable dead time during interrogation. Here we measure the phase noise of the interrogation oscillator applied in the microwave frequency standard based on laser-cooled 113^Cd＋ ions, and analyze the Allan deviation limited by the Dick effect. The results indicate that the Dick effect is one of the key issues for the cadmium ion dock to reach expected frequency stability. This problem can be resolved by interrogating the local oscillator continuously with two ion traps.

Delay Effect on Coherent Transfer of Optical Frequency Based on a Triple-Pass Scheme

We demonstrate a triple-pass scheme for coherent transfer of optical frequency and the delay effect on the fiber phase noise compensation. It is theoretically proved that the delay effect consists of both fiber delay and servo delay. The delay effect confines the servo bandwidth within 1/8 and induces a residual fiber phase noise after noise compensation. For a 25-km-long fiber, the servo bandwidth is found to be around 1 k Hz, and the fiber phase noise is suppressed approaching to the theoretical limitation. The triple-pass scheme enables the simultaneous transfer of optical frequency to multiple remote users. The performance of noise compensator in the triple-pass scheme can achieve a similar level result compared with that in the double-pass scheme.

A Reconstruction and Discussion of the Effect of Diagenetic Environment on Hydrocarbon Generation Based on Diagenetic Mineral Assemblage in Mudstone

Inorganic minerals in mudstone are composed of clay minerals,carbonate and detrital minerals.Detrital minerals(such as quartz and feldspar)are mainly original deposit.However,clay minerals(kaolinite,illite,and chlorite)and carbonate(calcite and dolomite)are mostly diagenetic minerals.Furthermore,conversion of the four kinds of clay minerals are common.The formation of clay minerals and carbonate is controlled by temperature,pressure,p H,Eh and type of cations during diagenesis.Therefore mineral assemblage can indicate the characteristics and change of diagenetic environment.In addition to inorganic minerals,there are also organic matter of different sources and chemical properties in mudstone.Traditionally,it is considered that evolution of organic matter is controlled by thermal effect.Now studies show that inorganic and organic matter can interact with each other and form clay-organic complexes.This suggest that attention should be paid to the influence of diagenetic mineral assemblage and diagenetic environment on the evolution of organic matter* Samples of mudstone from 1500-4500m of the Palaeogene in the Dongying Depression,China,were collected to investigate the changes of mudstone diagenetic environment.XRD,thin section and SEM were used to detect diagenetic minerals and assemblage characteristics.Results showed that content of detrital minerals,which are floating in mud matrix or preserved as silt laminae,is basically unchanged from shallow to deep strata.Clay minerals which are gathered as argillaceous matrix or preserved as argillaceous laminae have growth and decline relation to carbonate which mainly appear as micropoikilitic ferriferous calcite and ferriferous dolomite.All these characteristics indicate that detrital minerals are exogenetic,whereas carbonate is diagenetic minerals.Based on the SEM analysis of the clay minerals,it was found that smectite present honeycomb and reticulate structure,while illite present filiform and schistose structure and there are growth and decline relationship between them.Nevertheless,hexagonal tabular and stratified kaolinite has the highest content from 2400m to3300m.Rosette and stratified chlorite shows increase trend when the burial depth is deeper than 3300m.These characteristics indicated that clay minerals are diagenetic minerals and there are conversions among the four types.Therefore form shallow to deep,three diagenetic mineral assemblage zones can be divided based on the characteristics of carbonate and clay minerals in mudstone.Namely,smectite+illite/smectite zone in the depth of 2000-2500m;kaolinite+illite/smectite zone in the depth of 2500-3300m and illite+chlorite+carbonate zone below 3300m.Previous studies showed that kaolinite is stable under acidic conditions,while other clay minerals and carbonate are stable under alkaline conditions.Hence according to mineral assemblages feature,it was inferred that diagenetic environment of mudstonehasundergonethechangeof alkaline-acid-alkaline.For the organic matter with different chemical properties in mudstone,the hydrocarbon generation will be different in the acidic and alkaline diagenetic environment even if the conditions of temperature and pressure are the same.Therefore,for hydrocarbon generation we should not only focus on thermal effect,but also pay more attention to the differences of diagenetic environment which have great significance for the understanding of hydrocarbon generation,hydrocarbon expulsion and reservoir formation in mudstone.

Predicting air pressure in drainage stack of high-rise building

It is necessary to understand the features of air pressure in a drainage stack of a high-rise building for properly designing and operating a drainage system. This paper presents a mathematical model for predicting the stack performance. A step function is used to describe the effect of the air entrainment caused by the water discharged from branch pipes. An additional source term is introduced to reflect the gas-liquid interphase interaction （GLII） and stack base effect. The drainage stack is divided into upper and base parts. The air pressure in the upper part is predicted by a total variation diminishing （TVD） scheme, while in the base part, it is predicted by a characteristic line method （CLM）. The predicted results are compared with the data measured in a real-scale high- rise test building. It is found that the additional source term in the present model is effective. It intensively influences the air pressure distribution in the stack. The air pressure is also sensitive to the velocity-adjusting parameter （VAP）, the branch pipe air entrainment, and the conditions on the stack bottom.

Direct carboxylation of thiophene with CO_(2) in the solvent-free carboxylate-carbonate molten medium:Experimental and mechanistic insights

A feasible synthesis route is devised for realizing direct carboxylation of thiophene and CO_(2) in a relatively mild solvent-free carboxylate-assisted carbonate(semi)molten medium.The effects of reaction factors on product yield are investigated,and the phase behavior analysis of the reaction medium is detected through the thermal characterization techniques.Product yield varies with the alternative carboxylate co-salts,which is attributed to the difference in deprotonation capacity caused by the base effect within the system.Besides,the detailed mechanism of this carbonate-promoted carboxylation reaction is studied,including two consecutive steps of the formation of carbanion through breaking the C-H bond(s)via the carbonate and the nucleophile attacking the weak electrophile CO_(2) to form C-C bond(s).The activation energy barrier in C-H activation step is higher than the following CO_(2) insertion step whether for the formation of the mono-and/or di-carboxylate,which is in good agreement with that of kinetic isotope effect(KIE)experiments,indicating that the C-H deprotonation is slow and the forming presumed carbanion reacts rapidly with CO_(2).Both the activation energy barriers in deprotonation steps are the minimal for the cesium cluster system since there have the weak the cesium Cs-heteroatom S(thiophene)and Cs-the broken proton interactions compared to the K2CO3 system,which is likely to enhance the acidity of C-H bond,lowering the C-H activation barrier.Besides,these mechanistic insights are further assessed by investigating base and C-H substrate effects via replacing Cs2CO3 with K2CO3 and furoate(la)with thiophene monocarboxylate(1b)or benzoate(1c).

International Transfer Pricing——A Generalziation Based on Income Tax and Tariff Effects

In order to successfully compete in the global market,many multinationalcompanies use control and evaluation systems for monitoring the performanceof their subsidiaries abroad,which are faced with complexities of political,social,cultural,and legal differences,tax regulations,import and export re-strictions,foreign exchange regulations,control on the transfer of f unds,and various other restrictions imposed by host countries to protect their nation-al interests.The challenge for multinationals is to design a transfer strategywhich appropriately rewards the management of the subsidiaries overseas andalso copes with the various poli tical,legal,cultural,and economic restric-tions of the host countries.

Current measurement method based on magneto-optic rotation effect

Aiming at the approximate measurement of magnetic rotation angle in optical current sensor based on light intensity detection mode,this paper proposes a current measurement method based on triangular constant transformation to reconstruct magnetic rotation angle,so as to avoid the large current measurement error caused by the approximate measurement of the magnetic rotation angle.By extracting the direct current(DC)component and the alternating current(AC)component of the light intensity signal detected by the photoelectric detector(PD),the sine signal containing the magnetic rotation angle is directly obtained by dividing the two components,and then the triangular identity transformation method is used to linearly demodulate the magnetic rotation angle and reconstruct the current waveform.The experimental results show that the relative error of current measurement does not exceed 1.40%in the current range of 0.05—0.50 A,which is less than the approximate linear measurement(ALM)method,and the magnetic rotation angle and the current have a good linear relationship.

Parameter analysis of a photonic crystal fiber with raised-core index profile based on effective index method

Photonic crystal fibers （PCFs） with a stepped raised-core profile and one layer equally spaced holes in the cladding are analyzed. Using effective index method and considering a raised step refractive index difference between the index of the core and the effective index of the cladding, we improve the characteristic parameters such as numerical aperture and V-parameter, and reduce its bending loss to about one tenth of a conventional PCF. Implementing such a structure in PCFs may be one step forward to achieve low loss PCFs for communication applications.

Improved third-order nonlinear effect in graphene based on bound states in the continuum

The scattering matrix theory has been developed to calculate the third-order nonlinear effect in sphere-grapheneslab structures. By designing structural parameters, we have demonstrated that the incident electromagnetic wave can be well confined in the graphene in these structures due to the formation of a bound state in the continuum(BIC) of radiation modes. Based on such a bound state, third-harmonic(TH) generation and four-wave mixing(FWM) have been studied. It is found that the efficiency of TH generation in monolayer graphene can be enhanced about 7 orders of magnitude. It is interesting that we can design structure parameters to make all beams(the pump beam, probe beam, and generated FWM signal) be BICs at the same time. In such a case, the efficiency of FWM in monolayer graphene can be enhanced about 9 orders of magnitude. Both the TH and FWM signals are sensitive to the wavelength, and possess high Q factors, which exhibit very good monochromaticity. By taking suitable BICs, the selective generation of TH and FWM signals for S-and P-polarized waves can also be realized,which is beneficial for the design of optical devices.

Design and fabrication of wavelength tunable AWGs based on the thermo-optic effect

In this Letter, a 16 channel 200 GHz wavelength tunable arrayed waveguide grating（AWG） is designed and fabricated based on the silicon on insulator platform. Considering that the performance of the AWG, such as central wavelength and crosstalk, is sensitive to the dimension variation of waveguides, the error analysis of the AWG with width fluctuations is worked out using the transfer function method. A heater is designed to realize the wavelength tunability of the AWG based on the thermo-optic effect of silicon. The measured results show that the insertion loss of the AWG is about 6 d B, and the crosstalk is 7.5 d B. The wavelength tunability of 1.1 nm is achieved at 276 m W power consumption, and more wavelength shifts will gain at larger power consumption.

Geoacoustic inversion based on reflection model of effective density fluid approximation

In order to obtain the physical and geoacoustic properties of marine sediments,an inverse method using reflection loss of different grazing angles is presented.The reflection loss is calculated according to the reflection model of effective density fluid approximation.A two-step hybrid optimization algorithm combining differential evolution and particle swarm optimization along with Bayesian inversion is employed in estimation of porosity,mean grain size,mass density and bulk modulus of grains.Based on the above physical parameters,geoacoustic parameters,including sound speed and attenuation,are further calculated.According to the numerical simulations,we can draw a conclusion that all the parameters can be well estimated with the exception of bulk modulus of grains.In particular,this indirect inverse method for bottom geoacoustic parameters performs high accuracy and strong robustness.The relative errors are 0.092%and 17%,respectively.Finally,measured reflection loss data of sandy sediments at the bottom of a water tank is analyzed,and the estimation value,uncertainty and correlation of each parameter are presented.The availability of this inverse method is verified through comparison between inverse results and part of measured parameters.

Research of whispered speech vocal tract system conversion based on universal background model and effective Gaussian components

Directing to the weakness of the present fixed values mapping methods （method_F）, a vocal tract system conversion method based on the universal background model （UBM） is proposed for improving the performance of the speech conversion system from Chinese whis- pered speech to normal speech. For the numerous components of UBM, the errors produced by the acoustical probability density statistical model can＇t be ignored. Thus an effective Gaus- sian mixture components chosen method based on the posterior probability summation of the minimum spectral distortion is developed to optimizing the system performance. The proposed method （method_U） is analyzed and compared using the performance index （PI） based on Itakura-Saito spectral distortion measure. It is shown experimentally that the performance of method_U is more stability for different speakers and different phonemes than that of method_F. The average PI of method_U is better than method_F. It is shown that by selecting effective Gaussian mixture components, the PI of method_U can be further improved 5.11%. Subjective auditory tests also show that the proposed method can improve the definition and intelligibility of conversion speech.

Syntheses and structures of tetranuclear Zn(Ⅱ) complexes with in situ generated macrocyclic Schiff base ligands:Applications in Zn^(2+) sensing

Three novel Zn（II） complexes,[Zn4L1Cl4]-3H2O（1）,[Zn4L2Cl4]-2DMF（2） and[Zn4L^3Cl4]H2O（3）,have been synthesized and structurally characterized.In these complexes,interesting 32-membered dodecadentate macrocyclic ligands were generated in situ by ＇2 ＋ 2＇ type condensation reactions between a tetraamine and various dialdehydes.All the complexes are isostructurally tetranuclear Zn（Ⅱ） complexes,containing endogenous alkoxo and phenoxo bridges.Applications of the macrocyclic ligands as Zn^2＋ sensors have been investigated.Take H4L^1 for example,it exhibits a 4-fold fluorescence enhancement upon the addition of 2 equiv.of Zn^2＋ in MeOH.

Tunable single-longitudinal-mode SOA-based fiber laser based on the spectral narrowing effect in a dispersion-shifted fiber

A tunable single-longitudinal-mode（SLM） semiconductor optical amplifier（SOA）-based fiber laser based on a dispersion-shifted fiber（DSF） is proposed and successfully demonstrated. SLM operation is obtained due to the spectral narrowing effect resulting from inverse four-wave mixing in a DSF. A tunable optical filter performs wavelength selection function. By inserting a length of DSF in the laser cavity, SLM lasing can possibly be obtained when laser oscillation is stably established after traveling through the DSF many roundtrips. Stable tunable SLM oscillation with a signal-to-noise ratio as high as 65 dB over a wavelength range of about 35 nm is achieved experimentally, and each spectral linewidth is less than 6.5 kHz.