政府副职分管结构与权力均衡的实证研究——以我国地级市副市长为例

副职是我国各级政府都设置的一个职位层级,但我们的关注焦点常常集中在正职身上而忽视了对副职群体的研究。本文通过对27个地级市的202位副市长的分管数据分析,发现常务副职的权力支配度是影响副职间权力均衡状况的关键,主要表现在常务副职所分管部门的数量和分管领域的重要程度上,其他副职之间的权力差异不大。当前我国副职的权力和职责范围具有严重的人格化倾向,完善分管型副职体制,还需要在权力结构设计和权力规范上作出进一步的调整。

Ultrastructural Studies on the Sieve Elements in Root Protophleom of Arabidopsis thaliana

The ultrastructures of the root protophleom sieve element at different developmental stages of Arabidopsis thaliana L. were investigated using the technique of high pressure freezing and freeze substitution fixing specimen. The results show that in the development of the sieve elements, the nuclei undergo typical characteristics of the programmed cell death (PCD): the nuclear envelopes form emboli, the chromatin condenses and aggregates towards the nuclear envelope, which degrades and fully disappears later. Before the nucleus degradation, neither the nuclear envelope undulation, nucleus lobe nor marked dilation (or bleb) of perinuclear space could be observed. In the cytoplasm of the mature sieve element, there are starch-like granules separately sheathed with a layer of membrane and usually with mitochondria around. These gnanules seem to provide substrates to mitochondria in their function. Small vacuoles originate from endoplasmic reticulum (ER), and no bigger vacuole was found.

Comparative Study on the Structural and Moisture Characteristics of Leaf from the Plantlets of Three Types of Ornamental Lilium brownii

[ Objective] The study was to compare the structural and moisture characteristics of leaf from the plantlets of three types of omamental lily（ Lilium brownii）. [ Method ] The paraffin sections of leaves of tested lily varieties were prepared and then observed under microscope, and the stomatal characteristics and moisture characteristics of tested lily varieties were measured. I Resaltl All the three ornamental lily varieties show isobilateral leaf, single layer of epicuticula and lower epidermis, and no obvious differentiation of palisade tissue and spongy tissue; their stomata distribute in lower epidermis, and the guard cells are dumbbell-shaped; all of these matedais present high moisture. For the leaf sick- ness, midrib sickness and mesophyll tissue sickness, the order was determined to be oriental lily 〉 Lilium/ongiflorum 〉 Asian lily; of the three types of ornamental lily, Ulium Iongiflorum has the largest stomatai aperture and Asian lily has the smallest; focusing the water potential and moisture, the turn was Asian lily 〉 oriental lily 〉 Lilium Iong＇fflorum. [ Condusion] The study may facilitate the artificial regulation of the growth conditions of the plantlets of ornamental lily.

A Broadband Long-Wavelength Superluminescent Diode Based on Graded Composition Bulk InGaAs

A novel unselective regrowth buried heterostructure long-wavelength superluminescent diode （SLD） with a graded composition bulk InGaAs active region is developed by metalorganic vapor phase epitaxy （MOVPE）. At a 150mA injection current, the full width at half maximum of the emission spectrum of the SLD is about 72nm, ranging from 1602 to 1674nm. The emission spectrum is smooth and flat. The ripple of the spectrum is less than 0.3dB at any wavelength from 1550 to 1700nm. An output power of 4.3mW is obtained at a 200mA injection current under continuous-wave operation at room temperature. This device is suitable for the applications of light sources for gas detectors and L-band optical fiber communications.

Structural Analysis of Peptides of PSⅡ Light-harvesting Complexes in Siphonous Green Algae, Codium fragile

Peptide composition and arrangement of 4 major light-harvesting complexes LHCP 1-3 and LHCP 3′ isolated from siphonous green algae (Codium fragile (Sur.) Hariot.) were investigated. LHCP 1 showed five main peptides, 34.4, 31.5, 29.5, 28.2 and 26.5 kD in SDS-PAGE, the 34.4 and 31.5 kD peptides were never found in higher plants. LHCP 3 contained the other four kinds of LHCP 1 peptides except 34.4 kD, while LHCP 3′ consisted of only 28.2 and 26.5 kD peptides. We found that 34.4, 28.2 and 26.5 kD peptides were easy to decompose from LHCP 1 when subjected to SDS-PAGE without pretreatment. They might be located at the exterior of LHCP 1, while the 31.5 and 29.5 kD peptides were at the central part. The 28.2 and 26.5 kD peptides often occurred in CPa, the center complex of PSⅡ. They are possibly the LHCⅡ peptides tightly associated with CCⅡ. According to the results described above, a peptide map of LHCP 1 was sketched.

Ultrastructural Observation of Changes of Polysaccharide Grains in Dormant Shoots of Eucommia ulmoides

Cytochemical and ultrastructural studies indicated that compound spherical bodies observed near the sieve plate in the sieve tube members during the period of cambial dormancy in the shoots of Eucommia ulmoides Oliv. were polysaccharide bodies different from the polysaccharide grains in other parenchyma cells in shoots, and were similar to cell walls in their staining properties. The compound spherical bodies occurred in the sieve elements during the period of cambial rest and disappeared in the sieve elements during the period of cambial quiescence and activity.

Molecular Dynamics Simulations of Silica Nanotube： Structural and Vibrational Properties Under Different Temperatures

Four-, six-, and eight-membered ring silica nanotubes at temperatures from 300 K to 1600 K are relaxed by classical molecular dynamics simulations with three potential models. The simulation results indicate that the stability of the end rings of the three silica nanotubes gradually decreases with increase in temperature. The validity of the vibrational features of silica nanotubes is shown by the vibrational density of states. Infrared spectra on the silica nanotubes under different temperatures are investigated. A detailed assignment of each spectral peak to the corresponding vibrational mode of the three nanotubes has been addressed. The results are in good agreement with the other theoretical and experimental

Finite Element Simplified Fatigue Analysis Method for a Non-tubular Joint of an Offshore Jacket Platform

This paper proposes the finite element simplified fatigue analysis method for fatigue evaluation of the composite non-tubular joint structure of an offshore jacket subjected to wave loads. The skirt pile sleeve of the offshore jacket, which had been in service, was taken as an example of the non-tubular joint structure. SACS software was used for global analysis of multi-directional wave loads for the jacket platform, and ALGOR software was used to build a finite element model, perform finite element analysis, post-process stress results for acquiring the stress range, and perform fatigue evaluation. The analysis results indicate that the extreme stress range is within the allowable stress range and meets the requirements of DNV code. That means the simplified fatigue analysis method is effective and can be used in fatigue design for the non-tubular joint structure of an offshore jacket.

A Modified Molecular Structural Mechanics Method for Analysis of Carbon Nanotubes

A modified molecular structural mechanics method, based on molecular mechanics and similar to the finite element method, was developed. The energy of a system was expressed by the force field functions of the molecular mechanics. Under the small deformation assumption and by the principle of minimum potential energy, the system function was established. The properties of tension and bending of single-walled carbon nanotubes were analyzed. The Young＇s modulus is about 0.36 TPa nm, which agrees perfectly with the results of previous analysis by other researchers. It is found, for the first time, that the Young＇s moduli, for Zigzag nanotubes, are different from each other when the system energy was expressed as the sum of two or three individual energy terms in molecular mechanics. Whereas, the Young＇s moduli were the same for the Armchair nanotubes. It is found, when simulating the bending, that the deflections are closer to the theoretical ones, of the classical elasticity, when the diameter of the carbon nanotube increases.

A User-Oriented Implementation of Risk Breakdown Structure in Construction Risk Management

The construction industry works under conditions of uncertainties and risks leading to poor performance, increased cost and time and decreased quality. In these conditions, the dynamic identification and assessment of project risks among a vary range of potential factors is considered of vital importance. The introduction of RBS （risk breakdown structure） as a hierarchically organized depiction of identified risks was considered a suitable tool in risk management, especially in construction, due to its many advantages in synthetic representation and dynamic nature. This paper presents a user-oriented implementation of RBS to assist the project managers in identifying and assessing potential risk factors affecting construction process. The evidential analogies between WBS （work breakdown structure） and RBS are captured and used in the proposed framework which interconnects them into a 2D （two dimensional） matrix used to associate risks to the specific project activities. The proposed framework is applied to a government funded design-bid-build project. The obtained results clearly demonstrate the advantages in identifying the most risky activities, as well as the most important risk factors affecting the whole project.

Thermal analysis of an innovative flat heat pipe radiator

An innovative flat heat pipe radiator was put forward, and it has the features of high efficiency of heat dissipation, compact construction, low thermal resistance, light weight, low cost, and anti-dust-deposition. The thermal analysis of the flat heat pipe radiator for cooling high-power light emitting diode （LED） array was conducted. The thermal characteristics of the flat heat pipe radiator under the different heat loads and incline angles were investigated experimentally in natural convection. An electro-thermal conversion method was used to measure the junction temperature of the LED chips. It is found that the integral temperature distribution of the flat heat pipe radiator is reasonable and uniform. The total thermal resistance of the flat heat pipe radiator varies in the range of 0.38-0.45 K/W. The junction temperatures of LED chips with the flat heat pipe radiator and with the aluminum board at the same forward current of 0.35 A are 52.5 and 75.2 ℃, respectively.

Distributed Cooperative Mechanism and Application for Monitoring of Urban Subway Construction

In this paper, combining the technologies of Computer Supported Cooperative Work （CSCW）, Workflow and Network, the authors aim to organize virtual distributed cooperative work environment （VDCWE） and expound the running mechanism of cooperative workflow and design its algorithm for monitoring of urban subway construction. And then a prototype system was built based on the above,capable of supporting user analyzing, dealing with and managing data of monitoring, and real-timely releasing corresponding information, providing interactive virtual and distributed coordination meet-environment, dynami-cally and transparently, in favor of clients＇ interoperaiility and solving practicing problems, and so on.

Seventy Years’“Micropedology”1938-2008:The Past and Future

Although the first microscopic observations on soils date already from the beginning of the twentieth century, the publication of Kubiena＇s book ＂Micropedology＂ in 1937 is considered as the beginning of this new scientific discipline. This first system for micromorphological descriptions of soils is considered as morphoanalytical, analysing the fabric according to pure morphological criteria. In a second period Kuniena used a morphogenetic approach, directly relating the global observed fabric to genetic soil horizons. This system, mainly limited to European soils, was in general use till the early nineteen-seventies. End of the nineteen-fifties non- genetic soil classification systems were developed （e.g. USDA）. This trend prompted R. Brewer to publish in 1964 a new morphoanalytical system for fabric analysis, used till the end of last century. Because of some inconsistencies in this approach, a working group of the ISSS published in 1985 a new set of morphoanalytical concepts and associated terminology （Bullock et al.）, in 2003 adapted and extended by Stoops. Several morphosynthetic systems, expressing a complete soil microfabric in a single （compound） term have been proposed, but none was really successful. In 1967 Kubiena introduced the term ＂micromorphometry＂ to name a new branch of micromorphology quantifying the soil fabric, mainly evaluating changes in porosity and structure resulting from soil management. The necessity of dearly defined concepts and terms for fabric analysis of soils and regoliths, even as a need for standardisation of quantitative methods, are discussed in the conclusions.

Multi-active region laser diode with a narrow beam divergence angle

A novel large optical cavity laser diode,which consists of multi-active regions cascaded together through tunnel junctions,is proposed.After growing the epi-layers with LP-MOCVD system on GaAs substrate,the ridge waveguide laser structure is fabricated,and it shows a transverse divergence angle as low as 14.4°.

Interaction of Methane with Single-Walled Carbon Nanotubes: Role of Defects,Curvature and Nanotubes Type

We investigate the interaction of single-walled carbon nanotubes （SWCNTs） and methane molecule from the first principles. Adsorption energies are calculated, and methane affinities for the typical semiconducting and metallic nanotubes are compared. We also discuss role of the structural defects and nanotube curvature on the adsorption capability of the SWCNTs. We could observe larger adsorption energies for the metallic CNTs in comparison with the semiconducting CNTs. The obtained results for the zig zag nanotubes with various diameters reveal that the adsorption energy is higher for nanotubes with larger diameters. For defected tubes the adsorption energies are calculated for various configurations such as methane molecule approaching to the defect sites pentagon, hexagon, and heptagon in the tube surface. The results show that the introduce defects have an important contribution to the adsorption mechanism of the methane on SWNTs.

Three-Dimensional Numerical Investigation of the Separation Process in a Vortex Tube at Different Operating Conditions

Air separators provide safe, clean, and appropriate air flow to engines and are widely used in vehicles with large engines such as ships and submarines. In this operational study, the separation process in a Ranque-Hilsch vortex tube cleaning （cooling） system is investigated to analyze the impact of the operating gas type on the vortex tube performance; the operating gases used are air, nitrogen, oxygen, carbon dioxide and nitrogen dioxide. The computational fluid dynamic model used is equipped with a three-dimensional structure, and the steady-state condition is applied during computations. The standard k-c turbulence model is employed to resolve nonlinear flow equations, and various key parameters, such as hot and cold exhaust thermal drops, and power separation rates, are described numerically. The results show that nitrogen dioxide creates the greatest separation power out of all gases tested, and the numerical results are validated by good agreement with available experimental data. In addition, a comparison is made between the use of two different boundary conditions, the pressure-far-field and the pressure-outlet, when analyzing complex turbulent flows in the air separators. Results present a comprehensive and practical solution for use in future numerical studies.

Study of Competitive Chelating Reaction between Lanthanum and Tribromoarsenazo in the Medium of Weak Acid by Capillary Zone Electrophoresis

Two kinds of metal chelates of rare earth elements reacted with tribrimoarsenazo formed under the condition of critic acid were observed by simultaneous technique of capillary electrophoresisphotothermal interference spectrometry. The tendency of the conversion between these chelates as functions of the mole ratio of the reagent and the metal, pH value and the elapsing time was investigated. Kinetic equation of competitive chelating reaction between the TBA-La (Ⅲ) and La (Ⅲ) -critic acid were established. It was found that the competitive chelating reaction follows secondorder kinetics, for this second-order reaction, k=5.55 L·mol-1·S-1.

Structural Insights on Internet Traffic:Community Overlapping and Correlations

There is an increasing number of Internet applications, which leads to an increasing network capacity and availability. Internet traffic characterisation and application identification are, therefore, more important for efficient network management. In this paper, we construct flow graphs from detailed Internet traffic data collected from the public networks of Internet Service Providers. We analyse the community structures of the flow graph that is naturally formed by different applications. The community size, degree distribution of the community, and community overlap of 10 Internet applications are investigated. We further study the correlations between the communities from different applications. Our results provide deep insights into the behaviour Internet applications and traffic, which is helpful for both network management and user behaviour analysis.

Accounting Regulation Research and Structuration Theory

This paper considers accounting regulation research from a structuration and cultural perspective. Therefore, accounting regulation research spans over three spheres of enquiry： （1） an accounting focus of standard-setting; （2） a cultural analysis in an empirical context; and （3） the use of a research methodology drawn from Anthony Giddens＇ structuration theory. In such approach, accounting regulation research analyzes the accounting regulation actors drawing upon the cultures in their standard-setting actions and interactions, referring to Giddens＇ three structural properties of meaning, power, and morality. The integration of these three spheres of enquiry is not entirely original. A few prior studies have similar combinations： Although they stress the uses and consequences of accounting systems in producing and reproducing organizational culture and negotiating meaning at the organizational level, this paper chooses the research approach of contextual analysis of accounting systems at more macro-societal and cultural levels. This different research interest and design provides this paper with its distinguishable characteristic from the prior similar studies.

Dynamic Analysis of Historical Brick Masonry House

Brick masonry constructions are very common in many areas in the world and their failure in earthquakes has been the cause of many deaths. Since human safety is main issue of disaster management, people are more concerned about the structural assessment and strengthening of those constructions. One historical brick masonry house located in Kathmandu world heritage site is modeled by FEM （finite element method） and analyzed in E1 Centro earthquake ground motions. Bricks are modeled as solid elements and the interfaces between the brick units are modeled as zero thickness joint elements. Then, non-linear analyses of the house are applied satisfying the famous Mohr-Coulomb failure criterion. The result shows that the house is very weak and sustains large deformation in El Centro 1940 Earthquake. A strengthening solution modifying the connections of existing elements and adding wooden frame inside the house can reduce the deformations significantly.