Is ozone trapped in the solid carbon dioxide polar cap of Mars?

Laboratory experiments show that solid carbon dioxide is an effective trap for ozone at temperatures as high as 156 degrees K. Ultraviolet reflection-absorption spectra of ozone in solid carbon dioxide at 127 degrees K indicate that the ozone observed over the polar cap of Mars may be trapped in solid carbon dioxide.     

Evidence for solid carbon dioxide in the upper atmosphere of Mars

The infrared spectra recorded by Mariner 6 and 7 show reflections at 4.3 microns. which suggest the presence of solid carbon dioxide in the upper atmosphere of Mars.     

Wood versus fossil fuel as a source of excess carbon dioxide in the atmosphere: a preliminary report

If the amounts of wood consumed in deforestation to increase agricultural land and as firewood in underindustrialized countries are added to the amount consumed by the money economies as forest products, the estimates of the net amount of wood removed from the biosphere in this century should be revised upward. The per capita ratio of the weight of carbon from net wood burned to the weight of carbon from fossil fuel burned in this century has been at least 0.1 and may have approached 1.0.     

Industrial emissions of carbon dioxide in the United States: a projection

Carbon dioxide builds up in the eartht's atmosphere principally from increased use of fossil fuels. Estimates of the escalating uses of fossil fuels in the United States, especially for the generation of electric power and in the internal combustion engine, show that by the year 2000 emissions will have increased approximately eighteenfold from 1890. In the period 1965 to 1985 an emission-rate increase of around 4.0 percent per year compounded is expected. The expected intrusion and expansion of nuclear power will tend to lower the rates of increase of emission after 1985. Increases in emission rates in the rest of the world will probably equal or exceed the values projected for the United States.     

Discovery of natural gain amplification in the 10-micrometer carbon dioxide laser bands on Mars: a natural laser

Fully resolved intensity profiles of various lines in the carbon dioxide band at 10.4 micrometers have been measured on Mars with an infrared heterodyne spectrometer. Analysis of the line shapes shows that the Mars atmosphere exhibits positive gain in these lines. The detection of natural optical gain amplification enables identification of these lines as a definite natural laser.     

基于土地利用的北方农牧交错区碳固定和土壤保持时空变化

为探讨农牧交错区土地利用变化及其对生态系统服务的影响,以内蒙古达茂旗为研究区,通过土地利用转移矩阵和变化动态度的计量,采用模型模拟生态系统服务碳固定、土壤保持功能的方法,分析2000—2015年该旗碳固定和土壤保持演变特征。结果表明：草地、未利用地和耕地是主要的土地利用类型,16年间,草地、建设用地、未利用地、林地面积明显增加,耕地面积显著减少。土地利用类型变化主要是从耕地向草地、从草地向建设用地转移。2000—2015年,全旗碳固定量从183.25万t减少到181.65万t,土壤保持量从170.58万t减少到107.32万t,这一变化主要是由于研究区草地质量的降低使得单位面积提供的生态系统服务减少。各土地利用类型提供的碳固定和土壤保持均表现为草地 > 耕地 > 未利用地 > 建设用地 > 灌木林 > 林地 > 盐碱地 > 水域 > 沙漠。综上,在今后的生态治理中,应考虑在扩大草地面积、保护农田的基础上,适度利用草地、农田等生产生活用地,提高草地质量,科学优化土地利用结构,保障生态系统良性演化,提高生态系统服务功能。     

Ionospheric Composition and Reactions: Our present knowledge of what ions are in the ionosphere, and why, is summarized

Recent measurements of ion densities in the ionosphere seem to be more or less compatible with current data for ion-molecule reaction rates in some parts of the ionosphere under conditions in which a steady state prevails. There is no such agreement for the upper ionosphere, where the densities of He(+) and H(+) are difficult to understand in terms of present concepts concerning the relevant production and loss processes. Sources of ionizing radiation are needed to explain night- time observations in the E region and perhaps also in the F region. The D region remains a poorly understood laboratory of negative-ion and positiveion chemistry, where neither observation nor theory is as yet adequate.     

Magnetic clusters on single-walled carbon nanotubes: the Kondo effect in a one-dimensional host

Single-walled carbon nanotubes are ideal systems for investigating fundamental properties and applications of one-dimensional electronic systems. The interaction of magnetic impurities with electrons confined in one dimension has been studied by spatially resolving the local electronic density of states of small cobalt clusters on metallic single-walled nanotubes with a low-temperature scanning tunneling microscope. Spectroscopic measurements performed on and near these clusters exhibit a narrow peak near the Fermi level that has been identified as a Kondo resonance. Using the scanning tunneling microscope to fabricate ultrasmall magnetic nanostructures consisting of small cobalt clusters on short nanotube pieces, spectroscopic studies of this quantum box structure exhibited features characteristic of the bulk Kondo resonance, but also new features due to finite size.     

实验大鼠、小鼠胚胎的缓慢冷冻和玻璃化冷冻的比较

对3日龄小鼠胚胎和5日龄大鼠胚胎进行了玻璃化低温保存和缓慢冷冻保存的比较研究,从经过超数排卵的小鼠和大鼠中收集到了1897个8－16细胞的胚胎,经筛选后将I级和Ⅱ级胚计1738个（91．62%）分别进行两种低温保存试验,并对其中的881个冷冻胚胎分阶段进行复苏,复苏率分别为65．03％（小鼠69．59％,大鼠60．46％）和68．45％（小鼠72．61％,大鼠64．29％）,两者间无显著性差异（P＞0．05）。在复苏在胚胎中,选择其中的488个胚胎进行移植试验,结果,玻璃化冷冻保存胚胎的移植的受孕率为39．47％（89／222）,缓慢冷冻保存胚胎的移植的受孕率为42．56％（115／266）,两种低温保存方法经方差检验也无显著性差异（P＞0．05）。     

氮输入影响滨海湿地碳循环过程的模拟研究:进展与展望

滨海湿地碳循环是控制全球碳储量的关键过程之一,受近岸水体富营养化引起的氮输入影响显著。然而氮输入影响滨海湿地碳循环的过程复杂,利用碳循环模型是研究这些过程的有效手段,在全球气候变化下,评估滨海湿地碳储蓄功能具有重要意义。本研究介绍了滨海湿地碳组分在大气-植被-水体-土壤不同界面间的迁移和转化,总结了氮输入影响碳循环各阶段的规律,发现碳储蓄和碳通量对氮输入的响应受多个因素的共同作用。在此基础上,阐述了目前发展比较成熟且同时具有碳、氮、水相关模块的碳循环主流模型,以及模型为适应湿地而做出的改进及其在湿地的应用情况,为利用模型模拟氮输入影响滨海湿地生态系统碳循环的相关过程提供参考。探讨了将模型应用于湿地,应注意潮汐过程对氮输入影响等相关发展方向,同时就如何减少模型模拟的不准确性等问题展开讨论,对未来的研究方向提出展望。图1表1参126     

Follicle-stimulating hormone secretion in the female rat: cyclic release is dependent on circulating androgen

In adult cyclic female rats, intravenous injections of an antiserum to testosterone prevented the continued increase in serum follicle-stimulating hormone (FSH) which normally occurs during the early morning hours of estrus. This treatment did not prevent the initial increases in serum FSH (and luteinizing hormone) which occur during the critical period (1400 to 2000 of proestrus), nor did it interfere with subsequent ovulation. These observations indicate the existence of two separate mechanisms for preovulatory FSH release in the rat and implicate circulating testosterone as the stimulus for continued secretion of FSH during estrus.     

价值认知对规模养猪户农业碳交易参与意愿及期望碳价的影响 ——以户用沼气CCER项目为例

促进规模养猪户参与碳交易对实现中国的"碳中和"和农民增收目标具有重要意义。基于计划行为理论,以户用沼气CCER项目为例,利用Heckman选择模型,运用定量和定性的研究方法,分析农业碳交易价值认知对规模养猪户参与该项目的影响,探讨利用农业碳交易项目减少农业碳排放、实现农民增收的可能路径。结果表明,规模养猪户对农业碳交易项目的市场价值认知有待加强,同时约有93.21%的样本规模养猪户表示愿意参与沼气CCER项目,其平均期望碳价为15.26元/t。市场价值认知有助于改善规模养猪户的参与意愿,而非市场价值认知则能提高规模养猪户参与农业碳交易后的期望碳价。未来拟扩大养殖规模、家中接入互联网和村庄认同度较高的规模养猪户更容易受到市场价值认知的影响,表现出更强的农业碳交易参与意愿;未来拟扩大养殖规模和村庄认同度较低的规模养猪户则更容易受到非市场价值认知的影响而表现出更高的期望碳价水平。因此,需要关注到价值认知的重要作用,有针对性地宣传农业碳交易项目的价值,从而保障该项目在农村地区更好地推广。     

胶东地区海岱龙山文化生业考古新证——山东青岛三官庙遗址浮选结果的考古学观察

对山东青岛市即墨区即墨古城改造项目三官庙遗址浮选结果鉴定分析显示,就植物性食物资源的获取模式来看,海岱龙山文化三官庙聚落先民的生业系统包括作为生产性经济的食物生产和作为攫取性经济的采集行为两大组成部分。基于食物生产的作物组合为粟、黍、小麦、大麦(青稞),在可能存在的多种作物种植体系中,粟作农业扮演着更为重要的角色;其他植物遗存暗示了先民对其他植物资源利用的可能。本次浮选为胶东地区海岱龙山文化先民农业经济、生业模式提供了新证。     

大学语文,路在何方? ——由A校几乎全面停开大学语文引发的思考

大学语文曾在A校颇受重视与欢迎,但由于无法达到科研的层面以及自身定位的失当,并受学校建设目标调整的影响,在新一轮修订的专业培养方案中,几乎遭遇全面停开,渐渐淡出各专业的课程体系.在认真反思的同时,应正确定位大学语文,呼吁政策扶持,并创办专门的大学语文研究期刊.     

基于碳氮稳定同位素技术探究太湖北部湖区鲢、鳙食性差异

为探究太湖北部湖区4个不同水域鲢Hypophthalmichthys molitrix、鳙Aristichthys nobilis食性的差异,运用碳氮稳定同位素技术对太湖竺山湖、月亮湾、三国城和乌龟山水域的鲢、鳙、悬浮颗粒有机物(SPM)和水华蓝藻的δ13C和δ15N值进行了分析研究。结果表明:各个湖区SPM与水华蓝藻的δ13C差值为0.1‰¹.5‰,δ15N差值为0.3‰1.5‰,δ15N差值为0.3‰¹.6‰,单因素方差分析表明,SPM与水华蓝藻的δ13C和δ15N值均无显著性差异(P>0.05),说明SPM主要组分是水华蓝藻;水华蓝藻的δ15N值为12.8‰1.6‰,单因素方差分析表明,SPM与水华蓝藻的δ13C和δ15N值均无显著性差异(P>0.05),说明SPM主要组分是水华蓝藻;水华蓝藻的δ15N值为12.8‰¹5.8‰,均高于污染较小水域浮游植物的δ15N值(2‰15.8‰,均高于污染较小水域浮游植物的δ15N值(2‰⁸‰),说明这4个水域氮源污染仍比较严重;鲢、鳙的食性在4个水域内有一定的差异,除乌龟山水域鲢、鳙营养级有显著性差异(P<0.05)外,其他水域鲢、鳙的营养级均无显著性差异(P>0.05)。研究表明,竺山湖、月亮湾、三国城3个水域鲢、鳙在水华蓝藻爆发高峰期食物组成相似,摄食以水华蓝藻为主;月亮湾水域鲢、鳙的营养级均高于其他3个水域,可能是由于该水域的鲢、鳙在摄食蓝藻的同时,也摄食了少量的浮游动物,但对于其具体食物组成仍需要进一步研究。本研究结果能帮助揭示太湖北部不同水域鲢、鳙的主要食物来源为悬浮颗粒有机物,并分析悬浮颗粒有机物的主要来源为水华蓝藻,进而能够为利用鲢、鳙控藻和水资源的可持续利用提供一定的理论依据。     

基于碳氮稳定同位素技术探究太湖北部湖区鲢、鳙食性差异

为探究太湖北部湖区4个不同水域鲢Hypophthalmichthys molitrix、鳙Aristichthys nobilis食性的差异,运用碳氮稳定同位素技术对太湖竺山湖、月亮湾、三国城和乌龟山水域的鲢、鳙、悬浮颗粒有机物(SPM)和水华蓝藻的δ13C和δ15N值进行了分析研究。结果表明:各个湖区SPM与水华蓝藻的δ13C差值为0.1‰~1.5‰,δ15N差值为0.3‰~1.6‰,单因素方差分析表明,SPM与水华蓝藻的δ13C和δ15N值均无显著性差异(P0.05),说明SPM主要组分是水华蓝藻;水华蓝藻的δ15N值为12.8‰~15.8‰,均高于污染较小水域浮游植物的δ15N值(2‰~8‰),说明这4个水域氮源污染仍比较严重;鲢、鳙的食性在4个水域内有一定的差异,除乌龟山水域鲢、鳙营养级有显著性差异(P0.05)外,其他水域鲢、鳙的营养级均无显著性差异(P0.05)。研究表明,竺山湖、月亮湾、三国城3个水域鲢、鳙在水华蓝藻爆发高峰期食物组成相似,摄食以水华蓝藻为主;月亮湾水域鲢、鳙的营养级均高于其他3个水域,可能是由于该水域的鲢、鳙在摄食蓝藻的同时,也摄食了少量的浮游动物,但对于其具体食物组成仍需要进一步研究。本研究结果能帮助揭示太湖北部不同水域鲢、鳙的主要食物来源为悬浮颗粒有机物,并分析悬浮颗粒有机物的主要来源为水华蓝藻,进而能够为利用鲢、鳙控藻和水资源的可持续利用提供一定的理论依据。     

尚金:无情最是黄金物--20世纪中国市民文学文化价值观研究之一

在20世纪的市民文学中,"尚金"成为它的文化价值观的主脑,它是一把两面都锋利无比的双刃剑.作为市民文学的创作者和出版发行者,他们创作的目的和出版发行的目的都离不开商业性因素,把文学当成一种商品,把创作和出版发行当作一种挣钱的手段、谋生的方式,在他们是一种自觉的行为,明确的意识.在市民文学的文本世界中,金钱亦是主脑,它成为创作的动力、作品表现的题旨、情节结构的枢纽和支撑点、人物性格的驱动力、叙述的主脑.