浅谈提高课堂教学效果的方法与体会

随着改革开放的顺利进行,一切不适合于社会发展的事物逐渐被取代,高等院校也是如此。毕业分配的“双向”选择,就是高校改革的一个缩影,它不仅检验高校办学水平,而且也是高校得以发展的动力。试想,如果一个高校的60％—70％毕业生,在这种选择中,不能被社会企业集团所承认,那么,结果将是什么呢?相反,若毕业生供不应求,那将又会出现什么情况?

承认“特权”

我们搞了十几年的反腐败,有些问题是反掉了,还有些问题收效甚微,愈演愈烈。这结果,是增强了人们对腐败的适应力,提高了人们的容忍度,因而不满的怨气也自然少一点了,比如对于利用职权,提拔、任用关系人,就是一种。

浅析私立学校之存在

发展私立教育是我国教育体制改革的重要内容,本文分析了私立学校在一定范围内存在的必然性、可行性,在肯定私立学校的特点和作用的同时。又正视存在问题,为使其健康发展,急需立法,正确引导,加强管理。研究此课题,对推动办学机制的转换。促进教育改革的深入有着重要意义。

Kinetic Characteristics of Nitrate Uptake by Wheat and Rape and Their Determination

15-day old seedlings of wheat and rape were grown in a series of solutions with different concentrations of KNO3 for a definite period of time. The changes in NO3- concentration of the solutions were determined by the double ion-selective electrode method, and then the amount of NO3- taken up by the plants was estimated and values of Km and Imax of the Michealis-Menten equation were calculated. Results show that both the method and conditions of determination affected the values of Km and Imax. For example, the Km value was appreciably reduced when the volume of culture solution was increased or when the duration of nutrient uptake was shortened; the Km value obtained with short-term depletion method was higher than that obtained with long-term one. Similar Variations were found for the values of Imax. There was a considerable difference in the characteristics of uptake kinetics between wheat and rape when determined under the same conditions of determination. The isotherm of NO3- uptake by wheat could be separated into saturated and unsaturated parts, and when the concentration of NO3- exceeded 180 uuuuuuuuuuuuM, the relationship between the rate of NO3- uptake and NO3- concentration tended to be linear. However, the isotherm of NO3- uptake by rape was found to fit the Michealis-Menten equation and no linear relationship could be found.

Adsorption Kinetics of Pb^(2+) and Cu^(2+) on Variable Charge Soils and Minerals: Ⅲ. Adsorption Kinetics of Pb^(2+) Within 30 Minutes

The adsorption kinetics of Pb^2+ on different soils and minerals with variable charges was studied by the two ion-selective electrode technique at different pH and concentrations.The results showed that more than 95% of adsorption on all the samples occurred during the first 5 minutes.All adsorption time-dependent data could fit the surface second-order equation very well.The values of Xm were goethite>kaolinite,and latosol>red soil at the same initial reaction concentration.The values of k were kaolinite>>goethite,and latosol>red soil at the same reaction pH and initial concentration.The higher the suspension pH,the faster the adsorption occurred.The meaning of Xm got by the two ion-selective electrode technique(one kind of batch technique) was different from that by the miscible displacement technique in that the former was only the equilibrium adsorption amount at a definite concentration and pH,but the latter was almost equal to the adsorption capacity at a definite pH with much less influence of concentration.One Pb^2+ was supposed to occupy two adsorption sites as the adsorption mechanism is concerned.

Responses to two-way selection on growth in mass-spawned F_1 progeny of Argopecten irradians concentricus(Say)

In the present study, the effect of one-generation divergent selection on the growth and survival of the bay scallop （Argopecten irradians concentricus） was examined to evaluate the efficacy of a selection program currently being carried out in Beibu Bay in the South China Sea. A total of 146 adult scallops were randomly selected from the same cultured population ofA. i. concentricus, and divided into two groups in shell length （anterior-posterior measurement）： large （4.91-6.02 cm, n=74） and small （3.31-4.18 cm, n=72）. At the same time, a control group was also randomly sampled （4.21-4.88 cm, n=80）. Mass-spawned F1 progenies from the three size groups were obtained and reared under identical conditions at all growth phases. The effects of two-way （or upward-downward） selection on fertilization rate, hatching rate, survival rate, daily growth in shell length and body weight were assessed in the three size groups. Results show that significant differences （P〈0.01） were found in hatching rate, survival rate and daily growth of F~ progenies, but not in fertilization rate （P〉0.05）, among the three groups. The hatching rate, survival rate and daily growth of the progeny of large-sized parents were greater than those of the control group （P〈0.05）, which in turn were larger than those of small-sized group （P〈0.05）. Responses to selection by shell length and body weight were 0.32±0.04 cm and 2.18±0.05 g, respectively, for the upward selection, and -0.14±0.03 cm and -2.77±0.06 g, respectively, for the downward selection. The realized heritability estimates of shell length and body weight were 0.38±0.06 cm and 0.22±0.07 g for the upward selection, and 0.24±0.06 cm and 0.37±0.09 g for the downward selection, respectively. The change in growth by bidirectional selection suggests that high genetic variation may be present in the cultured bay scallop population in China.

Growth Performance of Larval and Juvenile Manila Clam(Ruditapes philippinarum) from Divergently Selected Individuals of a Full-Sib Family

Abstract In this study, the method of divergent selection was employed to test the larval and juvenile growth performance within a full-sib family of Manila clam Ruditapes philippinarum. The 10% largest and 10% smallest clam individuals （on the basis of shell length） of a full-sib family were selected as parents for the fast and slow growing lines, respectively. The difference in shell length was significant among the three lines （fast, control, and slow） tested. The sequence of shell length were fast line 〉 control line 〉 slow line. The responses to selection, realized heritability, and genetic gain were 0.06%-0.81%, 0.04%-0.47% and 0.58%-18.89% in the fast direction, respectively; and were 0.14%-1.27%, 0.08%-0.73%, and 0.31%-49.03% in the slow direction, respectively. The re- suits suggested that there was a large portion of additive genetic variance affecting the growth in the full-sib family. Selection in the fast direction within the full-sib family would greatly improve the growth ofR. philippinarum.

林州市国税局狠抓队伍建设成绩显著

河南林州市国税局牢固树立“工作上水平,素质要先行”的指导思想,积极采取四项措施,全面加强队伍建设并取得了显著成效。 引入竞争机制,树立“危机感”。该局大胆将企业风险机制和市场竞争机制引入队伍建设中,先后对40个中层领导职位实行了竞聘上岗,对一般人员岗位实行公开竞争,择优上岗,对人员岗位轮换实行“双向”选择,同时大力推行人员竞争上岗、待岗、辞退淘汰三项制度,从而彻底打破了原有封闭的人事管理体制,建立了“干部能上能下,人员能进能出”的新机制,大大激发了人们“居安思危,加压奋进”的危机意识和工作激情,为队伍建设带来了活力。