高房价“负效应”对我国青年一代的危害及对策研究

高房价是我国经济发展中最引人注目的热点问题,这个问题所产生的"负效应",不仅对我国经济和人民生活产生了极大影响;也对青年一代的择业、婚姻、生活和理想信仰等都产生了极大影响。本文首先从六个方面分析和论述高房价"负效应"对我国青年一代的影响,然后分析和提出遏制高房价和解决青年住房的几项具体措施。

数学插图“负效应”的分析及应对策略

当前,数学课本中插图使用的数量和形式越来越丰富,插图的使用固然会提高学生的学习效率,但是也不可避免地会产生一些不良影响。本文将在数学插图含义和作用介绍的前提下,分析数学插图可能存在"负效应"及应对策略。

极难选一水硬铝石型铝土矿反浮选脱硅的研究

为了解决细粒浮选的问题,本文作者采用一水硬铝石型铝土矿进行反浮选脱硅试验研究,并针对高硅型铝土矿首次提出了"强化二次富集"技术并将该技术成功地应用于实际矿石的浮选,达到了反浮选脱硅的目的。针对一水硬铝石型铝土矿试验结果表明:通过"强化二次富集"技术的应用,在不预先脱除矿泥的情况下直接进行铝土矿的反浮选试验,最终获得了满意的精矿指标:精矿铝硅比10.28,Al2O3回收率85.41%。

Study on Negative Effect Analysis of Mechanized Shattering and Returning for Sugarcane Leaf and its Control Technology

Soil structure and nutrient ingredient before and after shattering and returning sugarcane leaf as well as its technologies and methods were comparatively analyzed in this study to discuss the main reasons primarily,while the controlling technologies were proposed by combining cultivation,management and technical measures.

Negative effect improvement of accelerated curing on chloride penetration resistance of ordinary concrete

Four mineral admixture concrete specimens werefabricated to study the negative effect improvements ofaccelerated curing on the chloride penetration resistance ofordinary concrete. After reaching different initial strengths, the specimens were placed in 40, 60, or 80 t water tanks foraccelerated curing. The Coulomb values of the specimens weemeasured with ASTM C1202 experiment at 28, 100, 200, ad300 d. Partial specimens were also selected for rapid chlorideion migration coefficient and mercury intrusion porosimetryexperiments. The experimental results show that theaccelerated curing for ordinary concrete linealy deterioratesthe chloride penetration resistance, whereas the incorporationof mineral admixtures improves the concrete microscopic pore-structures and negative effects. An upper temperature limit of60 t of the accelerated curing is suitable for obtainingsuperior chloride penetration resistance for the mineraladmixture concrete. Pre-curing at a normal temperature of 20t is beneficial for improving the negative effect, which isalso aieviated with increasing testing age as a result of thesuccessive hydration of binder materials in concrete.

“阶层固化”、“渐进式”改革与现代化发展

在当前我国社会发展的转型期,社会阶层结构呈现出明显的"固化"态势,已成为我国现代化发展的重大潜在威胁。究其根源,我国社会的"阶层固化"现象是由取得阶段性成功的"渐进式"改革所产生的"负效应"造成的。在当前发展阶段和"渐进式"转型路径的约束下,面对日趋"固化"的社会阶层,只有协调、有序、配套地深化经济、政治和社会体制的改革,消除"渐进式"改革的"负效应",才能从根本上将社会"阶层固化"消除在萌芽状态。

浅析小学教育中的表扬

表扬是对过去和现在所取得的成绩的肯定，是认同别人的一种重要方式。表扬是对学生一种积极的认可、关注，也是一种促进。正确的表扬能带动学生的积极性，增强其自信心。当然，表扬有的时候也带有一定的“负效应”，如“骄傲”“自满”等。因此教育者一定要注意使用表扬这个教育方式，帮助学生树立自信和自尊，在讲究技巧的同时．

In Situ Experiments on Supporting Load Effect of Large-span Deep Tunnels in Hard Rock

A section of the Nanliang high speed railway tunnel on Shijiazhuang-Taiyuan high-speed passenger railway line in China was instrumented and studied for its mechanical properties and performances. The cross section for the tunnel was300 m2and is classified as the largest cross section for railway tunnels in China. Through in situ experimental studies, mechanistic properties of the tunnel were identified, including the surrounding rock pressure, convergences along tunnel perimeter and safety of primary support and lining structure.Based on the field measured data, the surrounding rock pressure demand for large-span deep tunnel in hard rock is recommended as double peak type in the vertical direction and fold line type was recommended for horizontal pressure. The results suggested that Promojiyfakonov's theory was most close to the monitored value. Specific recommendations were also generated for the use of bolts in tunnel structures.Numerical simulation was used to evaluate the safety of the tunnel and it confirmed that the current design can satisfy the requirement of the current code.

Bio-syngas Converting to Liquid Fuels over Co Modified Fe3O4-MnO2 Catalysts

A bifunctional Co modified Fe3O4-Mn catalyst was prepared for Fischer-Tropsch synthesis (FTS). The influence of Co loading on the synergistic effect of Fe-Co as well as FTS performance over Fe1CoxMn1 catalysts was studied. Incorporation of Co species into the Fe3O4-Mn catalyst promoted the reduction of iron oxides, increasing iron active sites during FTS. Moreover, the adding of Co species enhanced the electron transfer from Fe to Co metal, which strengthened the synergistic effect of Fe-Co, improving the catalytic performance. The Fe1CoxMn1 catalyst with higher Co loading promoted further the hydrogenation ability, favoring the shifting of the product distribution towards shorter hydrocarbons. Under optimized conditions of 280℃, 2.0 MPa and 3000 h-1, the highest yield of liquid fuels was obtained for the Fe1Co1Mn1 catalyst.

Quantum current and Coulomb blockade effect in the mutual inductance coupled mesoscopic system with active source

Based on the charge discreteness,the property of quantum current and the effects of Coulomb blockade have been investigated for the mutual inductance coupled mesoscopic system with active source in external magnetic field.The relationships between quantum current and the conditions of Coulomb blockade in the coupled dual-ring system are given here.

Support effect of the supported ceria-based catalysts during NH_3-SCR reaction

To investigate how the physicochemical properties and NH3‐selective catalytic reduction(NH3‐SCR)performance of supported ceria‐based catalysts are influenced as a function of support type,a series of CeO2/SiO2,CeO2/γ‐Al2O3,CeO2/ZrO2,and CeO2/TiO2catalysts were prepared.The physicochemical properties were probed by means of X‐ray diffraction,Raman spectroscopy,Brunauer‐Emmett‐Teller surface area measurements,X‐ray photoelectron spectroscopy,H2‐temperature programmed reduction,and NH3‐temperature programmed desorption.Furthermore,the supported ceria‐based catalysts'catalytic performance and H2O+SO2tolerance were evaluated by the NH3‐SCR model reaction.The results indicate that out of the supported ceria‐based catalysts studied,the CeO2/γ‐Al2O3catalyst exhibits the highest catalytic activity as a result of having a high relative Ce3+/Ce4+ratio,optimum reduction behavior,and the largest total acid site concentration.Finally,the CeO2/γ‐Al2O3catalyst also presents excellent H2O+SO2tolerance during the NH3‐SCR process.

Exploring the Low-Temperature Oxidation Chemistry of Cyclohexane in a Jet-Stirred Reactor:an Experimental and Kinetic Modeling Study

We report the investigation on the low-temperature oxidation of cyclohexane in a jet-stirred reactor over 500-742 K. Synchrotron vacuum ultraviolet photoionization mass spectrometry （SVUV-PIMS） was used for identifying and quantifying the oxidation species. Major products, cyclic olefins, and oxygenated products including reactive hydroperoxides and high oxygen compounds were detected. Compared with n-alkanes, a narrow low-temperature window （-80 K） was observed in the low-temperature oxidation of cyclohexane. Besides, a kinetic model for cyclohexane oxidation was developed based on the CNRS model [Combust. Flame 160, 2319 （2013）], which can better capture the experimental results than previous models. Based on the modeling analysis, the 1,5-H shift dominates the crucial isomerization steps of the first and second O2 addition products in the low-temperature chain branching process of cyclohexane. The negative temperature coefficient behavior of cyclohexane oxidation results from the reduced chain branching due to the competition from chain inhibition and propagation reactions, i.e. the reaction between cyclohexyl radical and O2 and the de- composition of cyclohexylperoxy radical, both producing cyclohexene and HO2 radical, as well as the decomposition of cyclohexylhydroperoxy radical producing hex-5-en-l-al and OH radical.

Negative Differential Resistance and Spin-Filtering Effects in Zigzag Graphene Nanoribbons with Nitrogen-Vacancy Defects

We explore the electronic and transport properties of zigzag graphene nanoribbons （GNRs） with nitrogen-vacancy defects by performing fully self-consistent spin-polarized density functional theory calculations combined with non-equilibrium Green＇s function technique. We observe robust negative di erential resistance （NDR） effect in all examined molecular junctions. Through analyzing the calculated electronic structures and the bias-dependent transmission coefficients, we find that the narrow density of states of electrodes and the bias-dependent effective coupling between the central molecular orbitals and the electrode subbands are responsible for the observed NDR phenomenon. In addition, the obvious di erence of the transmission spectra of two spin channels is observed in some bias ranges, which leads to the near perfect spin-filtering effect. These theoretical findings imply that GNRs with nitrogenvacancy defects hold great potential for building molecular devices.

Enhancement of lithium storage capacity and rate performance of Se-modified MnO/Mn3O4 hybrid anode material via pseudocapacitive behavior

To improve rate and cycling performance of manganese oxide anode material,a precipitation method was combined with thermal annealing to prepare the Mn O/Mn3O4/Se Ox(x=0,2)hybrid anode by controlling the reaction temperature of Mn2O3 and Se powders.At 3 A/g,the synthesized Mn O/Mn3O4/Se Ox anode delivers a discharge capacity of 1007 m A·h/g after 560 cycles.A cyclic voltammetry quantitative analysis reveals that 89.5%pseudocapacitive contribution is gained at a scanning rate of 2.0 m V/s,and the test results show that there is a significant synergistic effect between Mn O and Mn3O4 phases.

A visible-light-active Au-Cu(Ⅰ)@Na_2Ti_6O_(13) nanostructured hybrid pasmonic photocatalytic membrane for acetaldehyde elimination

The present article reports a novel self‐standing nanostructured Au‐Cu(I)@Na2Ti6O13plasmonic photocatalytic membrane,which is prepared by a hydrothermal reaction followed by a simple subsequent heat treatment process.The morphological structure,elemental composition,crystalline phases,and optical properties of the membrane were studied in detail by field‐emission scanning electron microscopy,transmission electron microscopy,X‐ray photoelectron spectroscopy,X‐ray diffraction,and ultraviolet‐visible spectroscopy.Compared with that of a pure Na2Ti6O13membrane,the Au‐Cu(I)@Na2Ti6O13membrane displayed much higher photocatalytic activity for the decomposition of acetaldehyde,a typical volatile organic compound,under visible light illumination.It was found that the photocatalytic activity of the Au‐Cu(I)@Na2Ti6O13membrane increased as the amount of Au was increased.The membrane loaded with2.85wt%Au showed the highest photocatalytic activity in the decomposition of acetaldehyde of the investigated materials.We found that in the photocatalyst membrane,Na2Ti6O13acted as a support material,Au displayed plasmonic absorption,and Cu(I)behaved as a co‐catalyst.The present membrane materials can avoid the self‐aggregation typically observed during the course of photocatalytic reactions.As a result,they can be easily separated,recycled,and reactivated after their practical application,making these functional materials attractive for use in air cleaning applications.

Impact of Grouting and Loading of Building Construction on the Water Level of Tangshan Mine Well

The water level rising rate of Tangshan mine well significantly accelerated in 2010,and the ascensional range was obviously higher than that of the same period in previous years.From the view of groundwater dynamics and loading effects,and based on the water pumping( pouring) water test model and semi-infinite elastic space theory model under uniform load,the effects of grouting and loading of nearby building construction on the well water level were analyzed. Results show that grouting at a distance of 200 ~ 700 m to the well,with amount of 2500m3 per day and duration of 270 d,can cause an 8 ~ 11 m rise of well water level; and loading of large-area building construction can cause about a 4m rise of well water level. Through the analysis of these factors,we find that the water level anomalous rising of Tangshan mine well was relevant to grouting and loading of the nearby building construction. This study provides a scientific basis for anomalous rising analysis of water level of Tangshan mine well.

Distributional Effects of Transport Taxes： An Incidence Analysis

Wider use of economic instruments in the field of environmental and energy policy provides several benefits. These instruments not only create market-based incentives for environmentally friendly behaviors but also represent effective opportunities to collect revenues. In this context, energy and transport-related taxes play a major role, even if their extensive use has raised several concerns over equity issues. The main objective of the paper is to investigate the redistributive burden of existing transport taxes on Italian households. An incidence analysis is carried out on a sample of more than 23,000 Italian families for the year 2009. Some alternative policy options are also analyzed to provide some suggestions on how to countervail the potential negative regressive effects that might arise. We find that vehicle ownership taxes, if properly set, can represent a promising opportunity to blend together budget and equity needs. To obtain a better indication of the progressivity or regressivity of certain policy designs, we rely on some summary indexes, such as the Kakwani measure of progressivity and the Reynolds-Smolensky measure of redistributive capacity of a tax.

Analysis of the Modes of Vibration and Static Resistance of the Frame of a Stirred Tank

The present study focuses on the design and choice of materials （steels S355 and 45SCD6） of a chassis of stirred tank （with a variable filling rate） for use in the manufacturing of cosmetic products. This tank or trough will be submitted to important mechanical and thermal loads and pressure according to the various manufacturing processes. The authors propose a model of thermal and mechanical loads which takes into account the operating conditions of the tank. The analysis of the first 10 modes of vibration of the frame shows that the frequencies are much higher when the filling rate is high. They are higher for steel 45SCD6 than for the $355. The simulation results show that for a selected type of steel, the equivalent Von Mises stress increases along with increase in fill rates and thermal gradient. It appears that the influence of the thermal gradient is predominant. For both steels, the Von Mises equivalent stress is maximum in the beam 32 when the thermal gradient is at its lowest stage, and in the beam 40 for the greatest thermal gradient.

Finite element analysis of couple effect of soil displacement and axial load on single inclined pile

The couple effect of soil displacement and axial load on the single inclined pile in cases of surcharge load and uniform soil movement is discussed in detail with the methods of full-scale field tests and finite element method. Parametric analyses including the degree of inclination and the distance between soil and pile are carried out herein. When the displacement of soil on the left side and right side of a pile is identical, deformation of a vertical pile and an inclined pile is highly close in both cases of surcharge load and uniform soil movement. When the couple effect of soil displacement and axial load occurs, settlement of an inclined pile is greater than that of a vertical pile under the same axial load, and bearing capacity of an inclined pile is smaller than that of a vertical pile. This is quite different from the case when the inclined pile is not affected by soil displacement. For inclined piles, P-Δ effect of axial load would lead to a large increase in bending moment, however, for the vertical pile, P-Δ effect of axial load can be neglected. Although the direction of inclination of piles is reverse, deformation of piles caused by uniform soil movement is totally the same. For the inclined piles discussed herein, bending moment(-8 m to-17 m under the ground) relies heavily on uniform soil movement and does not change during the process of applying axial load. When the thickness of soil is less than the pile length, the greater the thickness of soil, the larger the bending moment at lower part of the inclined pile. When the thickness of soil is larger than the pile length, bending moment at lower part of the inclined pile is zero.