“一时”的语法意义与语义特征探析

现代汉语中,副词“一时”常位于谓词性成分之前作状语,来修饰句中成分。“一时”的语法意义是非人为控制的短时存在,有当前短时存在、偶发短时存在和心理短时转变三类。它在语义上呈现短时性、偶然性、消极性和不可控性的特征,在句子的内部组配上倾向于否定句,而较少出现于肯定句中。

时间副词“一时”的三类语法意义

时间副词“一时”细分为三类语法意义。一类表“短时存在”，凸显某行为或状态在一段短时间内维持不变。与“暂时”相比，此“一时”后动词所指行为状态的可控性弱、存在的时段更短、否定式更多、陈述更客观。二类表“瞬间突发”，凸显某行为或状态是在某种条件刺激下瞬间突发的反应；所叙事件具有突发性、非可控性；“一时”后动词具有“终结性”语义特征；“一时”句往往为语篇中的后续句。与前分句构成条件——结果关系。三类表“临时变异”，凸显某行为或状态发生的临时偶然性；可作为始发句用来表示其后续句所述现象的原因。三类“一时”应根据其自然度高低确定合适的教学顺序。

"暂时"和"一时"的异同考察

本文分析了"暂时"和"一时"在语义和句法方面的特点,并对二者进行了对比。指出了"暂时"和"一时"可互换的两个条件。

感冒一小时胶囊中黄芩苷在正常与发热大鼠体内动力学特点的比较

目的 :探讨感冒一小时胶囊中黄芩苷在正常和发热大鼠体内的代谢动力学。方法 :采用高效液相技术分别测定正常大鼠和干酵母致发热大鼠血浆中黄芩苷的含量 ,使用 3P87软件处理黄芩苷的时量数据 ,计算各药代动力学参数。结果 :在正常和发热大鼠体内 ,黄芩苷的达峰时间分别为 9.46± 1.69h和 7.2 0± 2 .74h( p =0 .12 ) ) ,峰值血药浓度分别为 1.44± 0 .3 9μg/ml和 1.0 9± 0 .44 μg/ml( p =0 .2 1) ,t1/ 2 (ke)分别长达 10 .89± 5 .87h和 16.60± 2 0 .88h ,t1/ 2 (ka)分别为 3 .85± 0 .94和 2 .3 5± 1.48(p =0 .0 9) ,CL/F值分别为 2 2 .12± 5 .3 7(mg/kg) /h( μg/ml)和 3 8.3 8± 2 2 .99(mg/kg) /h/( μg/ml) ( p =0 .16) ,AUC(O T)值分别为 2 .68± 5 .81( μg/ml) h和 16.12± 4.91( μg/ml) h(P <0 .0 5 )。结论 :发热明显降低黄芩苷在体内的AUC(O T) ,有加快黄芩苷吸收和消除的趋势。

Rapid analysis and identification for the alkaloids from Ranunculus japonicus by UPLC /Q-TOF-MS

To establish a rapid and effective method for analysis and identification of the alkaloids from Ranunculus japoni- cus Thunb by ultra-performance liquid chromatogaraphy with quadruple-time-of-flight mass spectrometry （UPLC/Q-TOF- MS） and discuss their fragmentation regularity, the UPLC/Q-TOF-MS was used to identify the alkaloids from Ranunculus japonicus Thunb by their MS data, tandem characteristic fragment ions and standards. In the end, 12 alkaloids were identi- fied from Ranunculus japonicus for the first time, and their fragmentation regularity was discussed. Thus, a rapid and effec- tive analysis and identification method for the alkaloids from Ranunculus japonicus by UPLC/Q-TOF-MS is established.

Effects of external stress aging on morphology and precipitation behavior of θ'' phase in Al-Cu alloy

The exposure of Al-5Cu alloy to an external stress with normal aging was carried out. The effects of external stress-aging on the morphology and precipitation behavior of θ＂ phase were investigated by transmission electron microscopy （TEM）, differential scanning calorimetry （DSC） and first principle calculation. The size of the θ＂ phase precipitated plates in stress-aging （453 K, 6 h, 50 MPa） is 19.83 nm, which is smaller than that of those present （28.79 nm） in stress-flee aging （453 K, 6 h）. The precipitation process of θ＂ phase is accelerated by loading external stress aging according to the analysis of DSC results. The apparent activation energy for the external stress-aging is 10% lower than the stress-free one. The first principle calculation results show that the external stress makes a decrease of 6% in the interface energy. The effects of the stress on aging process of the alloy are discussed on the basis of the classical theory. The external stress changes the morphology and precipitation behavior of θ＂ phase because the critical nucleation energy is decreased by 19% under stress aging.

Long-Lived Coherence Originating from Electronic-Vibrational Couplings in Light-Harvesting Complexes

We theoretically investigate the evolutions of two-dimensional, third-order, nonlinear photon echo rephasing spectra with population time by using an exact numerical path integral method. It is shown that for the same system, the coherence time and relaxation time of excitonic states are short, however, if the couplings of electronic and intra-pigment vibrational modes are considered, the coherence time and relaxation time of this vibronic states are greatly extended. It means that the couplings between electronic and vibrational modes play important roles in keeping long-lived coherence in light-harvesting complexes. Particularly, by using the method we can fix the transition path of the energy transfer in bio-molecular systems.

Stability of Difference Systems with Finite Delay

In this paper, the authors establish some theorems that can ascertain the zero solutions of systemsx(n+1)=f(n,x n)(1)are uniformly stable,asymptotically stable or uniformly asymptotically stable. In the obtained theorems, ΔV is not required to be always negative, where ΔV(n,x n)≡V(n+1,x(n+1)) -V(n,x(n))=V(n+1,f(n,x n))-V(n,x(n)), especially, in Theorem 1, ΔV may be even positive, which greatly improve the known results and are more convenient to use.

A Comparative Study of Methods for Delineating Sphere of Urban Influence: A Case Study on Central China

A number of urban and regional plans have been developed with the advancement of urbanization and regional integration, among which the delineation of sphere of urban influence and improvement of integration between the city and its hinterland have be- come vital important for guiding practices. In terms of delineating sphere of urban influence, existing studies have been focused on static study by using single year data or single method, resulting in a lack of time-series longitudinal analysis or comprehensive analysis based on multiple methods This study emphasizes on comparing two methods from both the theoretical and empirical perspective. Both gravity model and improwd field model are applied to the selected study area for measurements and comparison, to explore their strengths and weaknesses. A research framework for comprehensive analysis on delineating sphere of urban influence is proposed. In the end, the differences of deli：aeating methods are illustrated and the feasibility of comprehensive analysis is discussed. Recommendations are provided for selecting appropriate methods for delineating sphere of urban influence or developing regional hierarchy system plans and urban spatial structure schemes.

Parallel computation of unified finite-difference time-domain for underwater sound scattering

In this work, we treat scattering objects, water, surface and bottom in a truly unified manner in a parallel finitedifference time-domain （FDTD） scheme, which is suitable for distributed parallel computing in a message passing interface （MPI） programming environment. The algorithm is implemented on a cluster-based high performance computer system. Parallel computation is performed with different division methods in 2D and 3D situations. Based on analysis of main factors affecting the speedup rate and parallel efficiency, data communication is reduced by selecting a suitable scheme of task division. A desirable scheme is recommended, giving a higher speedup rate and better efficiency. The results indicate that the unified parallel FDTD algorithm provides a solution to the numerical computation of acoustic scattering.

A general solution and approximation for the diffusion of gas in a spherical coal sample

The square root relationship of gas release in the early stage of desorption is widely used to provide a simple and fast estimation of the lost gas in coal mines. However, questions arise as to how the relationship was theoretically derived, what are the assumptions and applicable conditions and how large the error will be. In this paper, the analytical solutions of gas concentration and fractional gas loss for the diffusion of gas in a spherical coal sample were given with detailed mathematical derivations based on the diffusion equation. The analytical solutions were approximated in case of small values of time and the error analyses associated with the approximation were also undertaken. The results indicate that the square root relationship of gas release is the first term of the approximation, and care must be taken in using the square root relationship as a significant error might be introduced with increase in the lost time and decrease in effective diameter of a spherical coal sample.

Idea and goals of environmental protection and ecological construction in the 11^(th) five-year plan period

In this paper, the executive of the 10th Five- Year Plan in the field of environmental protection and ecological constrution is reviewed, and the charactristics of economic growth and its environmental impact on the 11^th Five-Year Plan is forecasted and analyzed. A principal idea of eavironmental protection and ecological construction is put forward for the 11^th Five-Year Plan pertod： strensgthen the point treatment in key areas and set the main targets based on the idea. The relating countermeasures in national level are proposed as follows： set up appropriate ideas for official achievements by launching resources and environmental cost acconting; adjust the industrial struacture actively by industrial policies and strenuous work; develop circular economy, change the mode of environmental protecgon from end treatment to headstream and proeess control： strengthen the market mechanism in the process of pollution treatment, set up the system of ＂who treats who benefits＂ ; perfect interrelated laws and standards, strengthen the ability of environmental munagement; lay extra emphasis on two key targets： water pollution tretment in key river basins and management of the reserves; and combine the ecological consnuction and poverty alleviation in higher level.

Constitutive modeling and springback prediction of stress relaxation age forming of pre-deformed 2219 aluminum alloy

Stress relaxation ageing behavior of pre-deformed AA2219 is studied through stress relaxation age experiments and finite element(FE) simulation. The results show that the stress can promote the process of ageing precipitation, and shorten the time to reach the peak strength. Meanwhile,the residual stress and yield strength increase along with the increase in the initial stress. Based on microstructure evolution and ageing strengthening theory,a unified constitutive model is established and incorporated into the FE simulation model through a user subroutine. It is found that the relative error of the radius is 3.6% compared with the experimental result and the springback is 16.8%. This indicates that the proposed stress relaxation ageing constitutive model provides a good prediction on the springback of such stiffened panel during its ageing process.

The space time CE/SE method for solving one-dimensional batch crystallization model with fines dissolution

This article is concerned with the numerical investigation of one-dimensional population balance models for batch crystallization process with fines dissolution.In batch crystallization,dissolution of smaller unwanted nuclei below some critical size is of vital importance as it improves the quality of product.The crystal growth rates for both size-independent and size-dependent cases are considered.A delay in recycle pipe is also included in the model.The space–time conservation element and solution element method,originally derived for non-reacting flows,is used to solve the model.This scheme has already been applied to a range of PDEs,mainly in the area of fluid mechanics.The numerical results are compared with those obtained from the Koren scheme,showing that the proposed scheme is more efficient.

Remarks on the Total Angular Momentum in General Relativity

We verify that the total angular momentum 3-vector defined by the author [X. Zhang, Commun. Math.Phys. 206 (1999) 137] is equal to (0, 0, ma) forany time slice in both the Kerr and the Kerr-Newman spacetimes.

ROTATION CONSTELLATION FOR DIFFERENTIAL UNITARY SPACE-TIME MODULATION

A new constellation which is the multiplication of the rotation matrix and the diagonal matrix ac- cording to the number of transmitters is proposed to increase the diversity product, the key property to the performance of the differential unitary space-time modulation. Analyses and the simulation results show that the proposed constellation performs better and 2dB or more coding gain can be achieved over the traditional cyclic constellation.

Novel differential unitary space-time modulation schemes for fast fading channels

Differential unitary space-time modulation （DUSTM）, which obtains full transmit diversity in slowly fiat-fading channels without channel state iufonnation, has generated significant interests recently. To combat frequency-selective fading, DUSTM has been applied to each subcarrier of an OFDM system and DUSTM-OFDM system was proposed. Both DUSTM and DUSTM-OFDM, however, are designed for slowly fading channels and suffer performance deterioration in fast fading channels. In this paper, two novel differential unitary space-time modulation schemes are proposed for fast fading channels. For fast fiat-fading channels, a subatrix interleaved DUSTM （SMI-DUSTM） scheme is proposed, in which matrix-segmentation and sub-matrix based interleaving are introduced into DUSTM system. For fast frequency-selective fading channels, a differential unitary space-frequency modulation （DUSFM） scheme is proposed, in which existing unitary space-time codes are employed across transmit antennas and OFDM subcarriers simultaneouslv and differential modulation is performed between two adjacent OFDM blocks. Compared with DUSTM and DUSTM-OFDM schemes, SMI-DUSTM and DUSFM-OFDM are more robust to fast channel fading with low decoding complexity, which is demonstrated by performance analysis and simulation resuits.

Terahertz spectrum clustering of traditional Chinese medicine based on first derivative characteristics

In order to deal with the unclear absorption peak caused by the absorption peak overlap of traditional Chinese medicine(TCM)and other mixtures,a method of three unsupervised clustering algorithms as K-means,K-medoids and Fuzzy C-means(FCM)combined with the first derivative characteristics of terahertz absorption spectrum,is proposed to perform the terahertz spectra clustering of Sanchi and other three kinds of TCM compared with their easily-confused products(ECPs).These three unsupervised clustering methods complement the scope of the supervised learning classification method.The first derivative of the spectrum could amplify the difference in the absorption coefficient with different substances,so that the obvious absorption peak can be revealed.Experiments shows that these three clustering algorithms can achieve good results by combining the origin absorption coefficient with its first-order derivative as the characteristic data,and among which K-means does the best with the accuracy of95.32%.Compared with pure absorption coefficient data clustering,the accuracy in this study has been significantly improved,especially for the non-absorption-peak TCM classification.And the accuracy of K-means algorithm is improved by5.38%.Besides,clustering algorithms in this study have strong anti-interference ability to the error data.

LDPC based differential unitary space-frequency coding for MIMO-OFDM systems

This paper proposes a novel LDPC based differential unitary space-frequency coding (DUSFC) scheme for MIMO-OFDM systems when neither the transmitter nor the receiver has access to the channel state information (CSI). The new DUSFC strategy basically consists of coding across transmit antennas and OFDM tones simultaneously as well as differential modulation in the time-domain. It can fully exploit the inherent advantages provided by the multipath fading channels, resulting in a high degree of diversity. The state-of-the-art low-density parity-check (LDPC) codes are concatenated with our DUSFC as channel coding to improve the bit error rate (BER) performance considerably. Owing to the maximum multipath diversity and large coding advantages, LDPC-DUSFC strongly outperforms the differential unitary space-time coded OFDM techniques re- cently proposed in literature. The corresponding iterative decoding algorithm without channel estimation is finally provided to offer significant performance gain. Simulation results illustrate the merits of the proposed scheme.

Passive multiple reverse time migration imaging based on wave decomposition and normalized imaging conditions

With the development of seismic exploration,passive-source seismic data has attracted increasing attention.Ambient noise passive seismic sources exists widely in nature and industrial production.Passive seismic data is important in logging while drilling(LWD),large-scale structural exploration,etc.In this paper,we proposed a passive multiple reverse time migration imaging(PMRTMI)method based on wavefield decomposition and normalized imaging conditions method.This method differs from seismic interferometry in that it can use raw passive seismic data directly in RTM imaging without reconstruction of virtual active gather,and we use the wavefield decomposition method to eliminate the low frequency noise in RTM.Further,the energy normalized imaging condition is used in full wavefield decomposition,which can not only enhance the image quality of both edge and deep information but also overcome the wrong energy problem caused by uneven distribution of passive sources;furthermore,this method exhibits high efficiency.Finally,numerical examples with the Marmousi model show the effectiveness of the method.