高中热——新一轮职教改革的提示

高中热现象暴露了职教中潜伏已久的问题,它提醒人们:必须进一步深化职教改革.一、形势的变化,职教的困境我国职教的大发展始于七、八十年代之交.当时的背景有三个基本特点.首先,中等教育结构极端不合理.随着高考制度的恢复,普通中学迅速发展,而职业技术教育相对薄弱.自1978年提出要扩大职校比例起,经过四年多的努力,到1982年高中段职、普教在校生的比例也才只有1:5.其次。

一组高中热学是非判断题

一组高中热学是非判断题浙江省鄞县中学陈光荣“热学”研究的是热现象的规律及其应肌“热现象”指的是物体的物理性质随温度发生变化的现象．按照分子运动论的观点，热现象是与大量的微观粒子（分子、原子）的无规则运动密切相关的．为了弄清热现象的规律和本质，必然涉及...

职教课程“异化”现象之剖析

近年来由于高新技术的发展、人文观念的变更以及人才需求的高移等原因,在一些地区出现了一定程度的“高中热”,也就是说初中毕业生分流呈现出不均衡的“独木桥”现象。这一“热”也波及到职业教育,一部分中专、职校、技校为了适应这一社会普遍的需求以及自身的生存和发展,也相继实施“双证书”的职教活动,即学生在职校中同时实施高中课程的教学活动,或采用补充教材,或利用夜间和休息日加课以完善高中课程;也有的学校干脆在职教课程中直接引入“高中课程”,以适应“高中会考”而取得高中证书。这一现象我们暂且称之为“职教课程异化”,在此想对这一“异化”作些剖析。

Two new species of Sellaphora(Bacillariophyta) from a deep oligotrophic plateau lake,Lake Fuxian in subtropical China

We describe two new species of Sellaphora from Lake Fuxian, Ytmnan Plateau, China. Based on both light and scanning electron microscopy, these species are described as S. yunnanensis sp. nov. and S. sinensis sp. nov. The primary features of S. yunnanens＆ are： elliptical to linear-elliptical valves with broadly rounded ends, straight filiform raphe, almost straight central endings and small, slightly expanding central pores, small central area, symmetrical or slightly asymmetrical central nodule. The primary features of S. sinensis are： elliptical valves, obtusely rounded ends, similar raphe and axial area, transapically less expanded central area, larger, elliptical central nodule. We compare these species to those of a similar shape and morphology.

An Investigation of the Formation of the Heat Wave in Southern China in Summer 2013 and the Relevant Abnormal Subtropical High Activities

In the summer of 2013, an unprecedented heat wave was experienced over a vast area of southern China. The great areal extent, duration, and strength of this high temperature are very rare. For the 2013 hot spell, the major and direct influence mostly came from the anomaly of the western Pacific subtropical high(WPSH). The abnormally strong and stable WPSH was associated with specific surrounding circulations. The eastward extension of a stronger Qinghai-Xizang high favored the westward extension of the WPSH. The weaker cold air activity from the polar region led to the northward shift of the WPSH and helped it to remain stable. In the tropics, the western segment of the ITCZ was abnormally strong in the period, and supported the maintenance of the WPSH from the south. In addition, the interdecadal variation of the WPSH provided a decadal background for the anomaly variation of the WPSH that summer.

Hyperammonemia,brain edema and blood-brain barrier alterations in prehepatic portal hypertensive rats and paracetamol intoxication

AIM:To study the blood-brain barrier integrity,brain edema, animal behavior and ammonia plasma levels in prehepatic portal hypertensive rats with and without acute liver intoxication. METHODS:Adults male Wistar rats were divided into four groups.Group Ⅰ:sham operation;Ⅱ:Prehepatic portal hypertension,produced by partial portal vein ligation;Ⅲ: Acetaminophen intoxication and Ⅳ:Prehepatic portal hypertension plus acetaminophen.Acetaminophen was administered to produce acute hepatic injury.Portal pressure,liver serum enzymes and ammonia plasma levels were determined.Brain cortex water content was registered and trypan blue was utilized to study blood brain barrier integrity.Reflexes and behavioral tests were recorded. RESULTS:Portal hypertension was significantly elevated in groups Ⅱ and Ⅳ.Uver enzymes and ammonia plasma levels were increased in groups Ⅱ,Ⅲ and Ⅳ.Prehepatic portal hypertension (group Ⅱ),acetaminophen intoxication (group Ⅲ) and both (group Ⅳ) had changes in the blood brain-barrier integrity (trypan blue) and hyperammonemia.Cortical edema was present in rats with acute hepatic injury in groups Ⅲ and Ⅳ.Behavioral test (rota rod) was altered in group Ⅳ. CONCLUSION:These results suggest the possibility of another pathway for cortical edema production because blood brain barrier was altered (vasogenic) and hyperammonemia was registered (oltotoxic).Group Ⅳ,with behavioral altered test,can be considered as a model for study at an early stage of portal-systemic encephalopathy.

Analysis on the Genesis and the Omission of a Torrential Rain over Linqu on 9 July 2012

In order to further study the drop zone of torrential rain in Weifang and summarize the experience of forecasting torrential rain in the future,a special diagnosis analysis was made on the process of the torrential rain.The meteorological information comprehensive analysis and processing system（MICAPS） 3.1 was used to carry out the analysis of profile and sounding to the conventional meteorological data,and finally numerical weather prediction was tested,which got the reason of production and omission of torrential rain.The results showed that one of the important reason of the torrential rain was caused by the combined effects of the dry cold air brought by the middle latitude shortwave trough and the southwest warm wet airflow brought by the jet flow,and the terrain influence caused by the Yishan in southern Liju County and the water evaporation in Mihe River was also an important reason.The main reason for the omission of the rain was caused by the over dependent on the rainfall forecast of numerical products and neglected the evolution of small scale process as well as analysis of the physical quantity field.Therefore,it was very important to monitor the actual weather situation and analyze all kinds of physical quantities for forecasting torrential rain.Besides,the forecaster should improve their ability in revising the numerical weather prediction.

An interdecadal change of tropical cyclone activity in the South China Sea in the early 1990s

Tropical cyclone （TC） genesis in the South China Sea （SCS） during 1979-2008 underwent a decadal variation around 1993. A total of 55 TCs formed in the SCS from May to September during 1994- 2008, about twice that during 1979-1993 （27）. During the TC peak season （July-September, JAS）, there were 43 TCs fi＇om 1994-2008, but only 17 during 1979-1993. For July in particular, 13 TCs formed from 1994-2008, but there were none during 1979-1993. The change in TC number is associated with changes of key environmental conditions in atmosphere and ocean. Compared to 1979-1993, the subtropical high was significantly weaker and was displaced more eastward during 1994-2008. In the former period, a stronger subtropical high induced downward flow, inhibiting TC formation. In the latter period, vertical wind shear and outgoing longwave radiation all weakened. Mid-level （850-500 hPa） humidity, and relative vorticity were higher. Sea surface temperature and upper layer heat content were also higher in the area. All these factors favor TC genesis during the latter period. The decadal change of TC genesis led to more landfalling TCs in Southern China during the period 1994-2008, which contributed to an abrupt increase in regional rainfall.

Change in the Pore Structure of Carbon-Carbon Composites during Successive Stages of High-Pressure Impregnation and Heat Treatment

Pore structure of C/C （Carbon-Carbon） composite after several stages of pitch impregnation under the high pressure and heat treatment was investigated by means of low temperature nitrogen adsorption and the standard contact porosimetry. Total pore volume, pore size distribution and specific surface area were calculated for samples of composite after several successive stages of treatment. The radius of pores presented in the material changes from 1 nm to 90 tam. Total pore volume and specific surface area both decrease after successive stages of pitch impregnation under the pressure, whereas heat treatment up to 1,750 ℃ and 2,000 ℃ leads to creation of some porous space and pore volume expansion. The bulk porosity of C/C composite comes down from 33.7% to 13.7% after the serial stages of treatment and the specific surface area is reduced by half compared to the initial material.

Definition of the South China Sea summer monsoon onset

We analyze statistically different definitions of the South China Sea summer monsoon(SCSSM) onset are to establish a SCSSM onset time series that is more recognizable by a majority of indicators.With the acknowledged index,we determine a key area(105°E-112.5°E,7.5°N-12.5°N) and define the zonal wind component in this key area as a new SCSSM onset index,using daily mean reanalysis data of the National Center for Environmental Prediction/National Center for Atmospheric Research.The atmospheric circulations before and after the onset of the SCSSM determined using the index defined in this paper are preliminarily studied.Results show that the Somalia cross-equatorial flow is enhanced,the strongest westerly wind in the tropical Indian Ocean shifts northward,the cyclone couple in the Bay of Bengal and the Southern Hemisphere weaken and move eastward,convection over the South China Sea increases,and the subtropical high retreats from the South China Sea after the outbreak of the SCSSM.By analyzing the atmospheric circulation,it is found that in 1984 and 1999,the SCSSM broke out in pentads 29 and 23,respectively,which is consistent with the onset times determined using our index.

Geographical Variation in Oligochaete Density and Biomass in Subtropical Mangrove Wetlands of China

Oligochaetes play an important role in nutrient cycling and energy flow in benthic food webs as well as in mangrove wetlands. However, they have not been as extensively studied as other macrofaunal groups such as polychaetes, gastropods, bivalves, and crustaceans. Under the assumption that oligochaete density and biomass obey specific geographical distribution patterns in subtropical mangrove wetlands of China, we investigated these two parameters in the Luoyang Estuary of Quanzhou Bay, Zhangjiang Estuary and Gaoqiao mangrove wetlands. A geographical gradient in oligochaete density was present in Aegiceras corniculatum and Kandelia obovata habitats, whereby it decreased from lower latitudes to higher latitudes. Further, ANOVA tests on oligochaete distribution revealed that both oligochaete density and biomass were significantly influenced by region, season and region × season at the A. corniculatum and K. obovata habitats. The annual average oligochaete density and biomass at the A. corniculatum habitat were higher than that at the K. obovata habitat, in both the Luoyang and Zhangjiang estuaries. There were significant correlations between oligochaete density and biomass and sediment particle size parameters, confirming that sand, silt, and clay contents were the key environmental factors affecting oligochaete distribution.

Long-Term High-Temperature Oxidation of Alloys for Intermediate Heat Exchangers

Alloy 617 is the reference candidate material for high temperature components of gas-cooled reactors, like intermediate heat exchangers. Oxidation tests were performed with two heats of Alloy 617 up to 5000 hours at 950℃ under a simulated helium-cooled reactor environment. Post-treatment examination showed that all materials actually oxidized during the tests with the growth of a surface chromium oxide scale that includes titanium, formation of a carbide-depleted zone underneath the surface, and internal oxidation of aluminum. These oxidation-related phenomena are in good agreement with the data published in the 1980s for Alloy 617 in equivalent testing conditions and were used to assess the alloy corrosion performances. The oxidation kinetics was globally parabolic corresponding to the growth of the external oxide as well as to internal oxidation. In the given test environment, the parabolic rate constants are 0.00090 and 0.00058 mg^2·c^-4m·h^-1 for the two heats of Alloy 617.

中考选报:中职还是高中——2007年上海市中等职业教育招生的宏观环境分析

2007年中招工作第一阶段的任务已顺利完成。接下来广大应届初中毕业生将面临人生的一次重大选择:报考中职,还是升读高中?

适度发展普通高中规模加强薄弱高中建设

目前,社会上出现了“念高中热”,带来了普通高中学额剧增、班型过大、教师负担加重、学校管理困难等一系列矛盾。这给教育管理部门提出了一个新课题:如何适度发展普通高中规模,加强薄弱高中建设。 社会出现“念高中热”原因有三,其一是随着我国社会主义两个文明建设的发展,初中毕业生不能满足社会对人才的要求。其二是有些学校办学思想不端正,忽视学生职业技能的培养。

小议IPAD教学“反应热”实践案例

IPAD教学的亮点是教学的交互性和开放性、系统自动批改选择题作业并进行数据统计。"先学后教、当堂训练"的"洋思模式"的亮点是重能力、轻负担、提升后进生。本文尝试将IPAD和"洋思模式"进行整合优化的课堂实践案例。

Comparisons of JOULE 1 rocket thermospheric wind observations in high latitudes with GITM simulations

4 Summary and conclusion The JOULE sounding rocket 1 experiment was carried out at Poker Flat Research Range in Alaska around 1200 UT on March 27th,2003 with two instrumented rockets and one chemical tracer rocket.From the released TMA trails,neutral wind measurements from approximately 85 to 160 km altitude showed a vertically propagating wave and a jet structure around 120 km altitude.Large shears appeared at the bottom side of the jet with Richardson numbers close to or smaller than the critical value of 0.25,which implies the possible existence of Kelvin-Helmholtz instabilities caused by the vertical shear in the fast flows.