实用针对性——成人教育的关键

本院地学教学部一直开设“普通地质学”课程,是为中国科学院系统所招研究生中非地质专业新生增设的基础课。然而,这门课也吸引了不少的旁听生。在笔者执教的8个学期内,总听课人数为138人,平均每学期17.25人。在研究生院各科目中属于中等人数。其中在校研究生总共91人,占66％(约2/3),旁听生47人,占34％(约1/3)。旁听生中除1人为中学教师外,46人全为地矿部系统在职人员,最多的是地矿部文献情报中心(以“全国地质图书馆——地质情报研究所”为主,还有全国地质资料局),其     

Measurement and analysis of soil nitrogen and organic matter content using near-infrared spectroscopy techniques

Near infrared reflectance （N1R） spectroscopy is as a rapid, convenient and simple nondestructive technique useful for quantifying several soil properties. This method was used to estimate nitrogen （N） and organic matter （OM） content in a soil of Zhejiang Province, Hangzhou County. A total of 125 soil samples were taken from the field. Ninety-five samples spectra were used during the calibration and cross validation stage. Thirty samples spectra were used to predict N and OM concentration. NIR spectra of these samples were correlated using partial least square regression. The regression coefficients between measured and predicted values of N and OM was 0.92 and 0.93, and SEP （standard error of prediction） were 3.28 and 0.06, respectively, which showed that NIR method had potential to accurately predict these constituents in this soil. The results showed that NIR spectroscopy could be a good tool for precision farming application.     

Do oarsmen have asymmetries in the strength of their back and leg muscles?

The aim of this study was to establish whether asymmetry of the strength of the leg and trunk musculature is more prominent in rowers than in controls. Nineteen oarsmen and 20 male controls matched for age, height and body mass performed a series of isokinetic and isometric strength tests on an isokinetic dynamometer. These strength tests focused on the trunk and leg muscles. Comparisons of strength were made between and within groups for right and left symmetry patterns, hamstring: quadriceps ratios, and trunk flexor and extensor ratios. The results revealed no left and right asymmetries in either the knee extensor or flexor strength parameters (including both isometric and isokinetic measures). Knee extensor strength was significantly greater in the rowing population, but knee flexor strength was similar between the two groups. No difference was seen between the groups for the hamstring: quadriceps strength ratio. In the rowing population, stroke side had no influence on leg strength. No differences were observed in the isometric strength of the trunk flexors and extensors between groups, although EMG activity was significantly higher in the rowing population. Patterns of asymmetry of muscle activity were observed between the left and right erector spinae muscles during extension, which was significantly related to rowing side (P < 0.01). These observations could be related to the high incidence of low back pain in oarsmen.     

三代又红又专知识分子的典范(演讲辞摘要)

在从事科学史的研究中,我接触到关于科学家生平事业的大量材料,他们的优秀品质深深地感动着我。其中对我启迪最大的有三位大科学家,他们年龄都相差约20岁,正好是三代人,他们都经历了不同的时代,但都走上了又红又专的道路,堪为我们的楷模。 第一位是李四光,他生于1889年,1971年逝世。他经历了满清王朝、民国(包括北洋政府和国民党政府)和新中国三个时代。在前清时期,他年十有五而志于救国,留学日本,学习造船,又参加了旧民主主义革命。辛亥革命流产后,他再度出洋,到英国学地质。在“而立”之年,他取得了硕士学位,谢绝了外国老师留他继续攻博士和去殖民地矿山工作的“好意”,毅然回国。到北京大学任教,又创办并领导了中央研究院地质研究所,取得了辉煌的学术成就,培养大批科技人才。他为人正直,追求进步,向     

Is the occurrence of the sticking region the result of diminishing potentiation in bench press?

In this study we investigated if the occurrence of the sticking region was a result of diminishing potentiation (coinciding delayed muscle activation) or the result of a mechanically poor region in which the muscles can produce less force. A regular one-repetition maximum (1RM) free-weight bench press was compared with isometric bench presses performed at 12 different positions. A lower force at the sticking region compared to the other regions in the isometric bench presses would confirm the mechanically-poor-position hypothesis. Twelve resistance-trained males (age 21.7 ± 1.3 years, mass 78 ± 5.8 kg, height 1.81 ± 0.05 m) were tested in 1RM and in isometric contractions in bench press in 12 different positions, indicated by the vertical distance between barbell and sternum, covering the whole range of motion during the concentric phase. Barbell kinematics and muscle activity were registered. In both types of executions a region of lower force output was observed, which supports the mechanically-poor-position hypothesis. Electromyographic activity of four muscles showed the same pattern in the isometric and 1RM attempts. It was concluded that diminishing effect potentiation could not explain the existence of the sticking region.     

Assessing semantic-syntactic features of verbs from thirteen verb subsets

There are three major classes of verbs: intransitive, transitive, and linking. These three types of verbs can be divided into 13 semantic-syntactic subsets. Verbs within each subset give rise to sentences that have similar syntactic form, albeit a form distinct from that of sentences associated with other subsets. Preliminary research found that more than 90% of sentences written by children or for children contain verbs from 1 of the 13 verb subsets. The sentence form associated with each verb subset might be viewed as a "sentence template" that operationally defines a fixed set of 13 underlying semantic-syntactic relationships essential to communication. A strategy for assessing a child's knowledge of verbs from each subset is described.     

崇高风范亲切教导重读《再造中华辉煌——邓小平纪事》

崇高风范亲切教导重读《再造中华辉煌———邓小平纪事》●潘云唐在深情缅怀世纪伟人邓小平同志的日子里，重读中共党史出版社１９９４年出版的《再造中华辉煌———邓小平纪事》一书，感到分外亲切。这本书是由中共中央党史研究室倡仪、组织，在全国各省、自治区、直辖市...     

潜心研地质辛勤育英才--纪念地质教育家喻德渊先生百年华诞

原长春地质学院院长喻德渊先生是著名的地质学家和地质教育家,今年是他诞生一百周年.人们深情地缅怀他的光辉业绩和崇高风范.     

科学乎?迷信乎?

大约一年前在北京举行的科技普及与科教兴国研讨会上，科普大师们就科学普及和科学传播、反科学与反“科学主义”、科学与迷信，以及新闻的性质与功能等问题进行了认真研究和热烈讨论。大家对所谓“科学文化人”最近提出的若干“科普新见”给以有力的批判。