水泥工业3项国家环境保护标准发布

近来科学家发现，由于人类排放到大气层中的二氧化碳越来越多，使得树木植物生长得越来越快、越来越大。从热带雨林到英国的甜菜作物，各种各样的植物群落都出现了这种生长加速的现象。     

在化学小组中研究矿物肥料

最近四年来,我每年都向化学小组的学生介绍“矿物肥料”这一课题。我希望通过这一课题,使学生对各种肥料:氮肥、磷肥和钾肥有一个具体而完整的概念,让他们认识各种肥料,懂得各种肥料对植物生长和发育的影响,知道制备各种肥料的矿物原料及其工业制法。要达到这些目的,有下列各种方法:由小组成员阅读通俗科学读物,组织制备肥料及说明肥料对植物生长发育影响的实验,解答检验肥料的实验习题及有关的计算题,制备附有实物样品的图表,参观农业展览馆、工艺博物馆、生产肥料的工厂及使用肥料的农业化学站,并参加集体农庄及国营农场的劳动等。小组通常由九及十年级学生15—20人组成。为了进行实习作业,可将小组成员再分成小小组,每三人一个小小组。通常可由一部分小小组较深入地研究氮肥,另一部分——磷肥,第三部分——钾肥。在解答检     

一种用于空气中二氧化碳现场测定的新方法

一种用于空气中二氧化碳现场测定的新方法于爱民，杨广德，王锐，金钦汉（吉林大学化学系，长春１３００２３）关键词微波诱导等离子体，离子化检测器，气相色谱仪，二氧化碳二氧化碳在植物生长代谢及其生态平衡过程中起着重要作用，现场测定二氧化碳是目前农业、环境科学...     

造纸黑液制取胡敏酸铵

胡敏酸铵是具有类似植物生长刺激素作用的一种肥料,可以提早种籽发芽,促进根系发育,加强植物体内有机物的合成和积累,促进土壤有机质的分解与转化,有利于作物对可溶性养分的吸收,达到农作物增产的目的。在制浆造纸工业中,纤维原料经碱液蒸煮产生大量的黑液,如果直接排入江河,将会污染水源,危害农业和渔业的生产,造成严重的社会公害。在无产阶级文化大革命中,造纸行业广大职工大搞综合利用,利用硫酸盐制浆的黑液制成了农肥胡敏     

毛细管气相色谱法测定高纯度三十烷醇

正三十烷醇是一种新型植物生长激素。目前国内外已广泛研究和使用。但对三十烷醇产品定量分析还是值得研究的课题。 目前一般以蜂蜡为原料,经过皂化有机溶剂重结晶得到三十烷醇。定量分析多采用填充柱法,其分离效果较差,峰形不理想。我们改用甲基乙烯基     

新型绿色植物生长调节剂——芸苔素内酯的研究进展*

芸苔素内酯是一种新型绿色环保植物生长调节剂,具有促进植物生长、提高植物抗逆抗病能力、改善植物生长品质等多方面功能,被视为第六类植物生长激素。概述了芸苔素内酯的研究进展,介绍了芸苔素内酯在农业生产中的应用,为推动芸苔素内酯的广泛使用提供参考。     

莫尔法沉淀滴定测定肥料中氯化物含量

我国目前常见的掺和肥料是以尿素、磷胺和氯化钾为主要成分，并混有植物所需的其它微量元素。其中氯化钾含量直接影响肥效，若施钾肥不当时，氯含量偏高，可直接影响植物生长，大大减少农林作物的单产量。     

腐植酸类肥料的刺激作用

一、正在发展中的腐植酸类生长刺激剂肥料最近几年来,我国广大群众对腐植酸类刺激剂肥料进行了极其广泛的试验研究和大面积推广应用,取得了显著成果。作为刺激剂用的腐植酸肥料,要求溶解度大,因此只有腐植酸的碱金属盐,如腐钠,腐钾,腐铵等才能满足要求。常用的刺激剂肥料主要为腐钠。由于原料和生产方法不同,腐钠也有很多品种。腐钠生产的基本原理是用烧碱(或纯碱)将原料煤(泥炭、褐煤或风化煤)中的腐植酸转化成可溶性的钠盐,与不溶的残渣分离。一般农村生产腐钠的方法是将原料煤粉加碱液堆沤,或加稀碱液热煮,或冷浸抽提,都制得了质量较好的腐钠。在工厂生产腐钠是将碱抽提液经澄清,浓缩,     

聚碳酸亚环己酯及其制备技术研究进展

二氧化碳既(CO₂)是令人头疼的温室气体,更是有价值的碳资源,因此二氧化碳的固定和利用具有重要的理论与现实意义。以二氧化碳和环氧环己烷为原料合成的聚碳酸亚环己酯(PCHC)是一种新型的脂环类可生物降解聚酯材料,相比传统的二氧化碳-环氧烷聚合物,其机械和耐热性能更为优良,有望拓展脂肪类聚碳酸酯的使用范围。本文对PCHC的基本性能及潜在应用领域、合成工艺路线以及交替共聚反应催化剂的发展进行了综述,以期为优质PCHC材料的高效制备提供参考。     

新型植物生长调解剂1-甲基-3-氧乙酸吲唑的合成和应用

植物生长调解剂;吲唑衍生物;新型植物生长调解剂1-甲基-3-氧乙酸吲唑的合成和应用     

The Colloidal Stabilization of Carbon with Carbon: Carbon Nanobubbles as both Dispersant and Glue for Carbon Nanotubes

The superior physical properties of carbon nanotubes (CNTs) have led to their broad application. Intrinsically, CNTs tend to agglomerate from hydrophobic interactions, which is highly undesirable for solution processing and device fabrication. Commonly, a stabilizer consisting of organic surfactants or polymers is used to disperse CNTs. Recently, we synthesized nitrogen‐doped carbon hollow nanospheres (25–90 nm), termed carbon “nanobubbles”. They bear superior dispersability in water and distinctive graphitic order. Herein, we describe the nanobubble‐assisted dispersion of CNTs in aqueous solution upon sonication. This process relies on the π–π interaction between the two aromatic carbon nanostructures, which can process their carbon mixture in water into conductive filter membranes, ink, and discs. This stabilization can be extended to other aromatic carbons. In addition, the π–π interaction may create a new type of carbon p–n junction that can be used to improve charge separation.     

一维新型碳的同素异形体:碳链

碳链是一种完全一维的、具有电子轨道sp杂化结构的新型碳的同素异形体.正是由于碳链的独特的一维结构,使其拥有区别于富勒烯、石墨烯和碳纳米管的化学键,从而表现出更加优异的性能,如:理论预言碳链的机械强度是石墨烯的几倍;碳链的导热也类似于石墨烯和碳纳米管;碳链是具有直接带隙的半导体材料,且带隙的大小可以通过其长度来调控,其长...     

Adsorption of Carbon Dioxide on Activated Carbon

The adsorption of CO2 on a raw activated carbon A and three modified activated carbon samples B, C, and D at temperatures ranging from 303 to 333 K and the thermodynamics of adsorption have been investigated using a vacuum adsorption apparatus in order to obtain more information about the effect of CO2 on removal of organic sulfur-containing compounds in industrial gases. The active ingredients impregnated in the carbon samples show significant influence on the adsorption for CO2 and its volumes adsorbed on modified carbon samples B, C, and D are all larger than that on the raw carbon sample A. On the other hand, the physical parameters such as surface area, pore volume, and micropore volume of carbon samples show no influence on the adsorbed amount of CO2. The Dubinin-Radushkevich (D-R) equation was the best model for fitting the adsorption data on carbon samples A and B, while the Preundlich equation was the best fit for the adsorption on carbon samples C and D. The isosteric heats of adsorption on carbon samples A, B, C, and D derived from the adsorption isotherms using the Clapeyron equation decreased slightly increasing surface loading. The heat of adsorption lay between 10.5 and 28.4 kJ/mol, with the carbon sample D having the highest value at all surface coverages that were studied. The observed entropy change associated with the adsorption for the carbon samples A, B, and C (above the surface coverage of 7 ml/g) was lower than the theoretical value for mobile adsorption. However, it was higher than the theoretical value for mobile adsorption but lower than the theoretical value for localized adsorption for carbon sample D.     

Growth of Single-walled Carbon Nanotubes on Substrates Using Carbon Monoxide as Carbon Source

The growth of single-walled carbon nanotubes(SWCNTs) on substrates has attracted great interests because of the potential applications in various fields. Carbon monoxide(CO) was used as the carbon source for the growth of SWCNTs on silicon substrates. Random or oriented SWCNTs can be produced by varying the CO flow rate. When the flow rate of CO was as low as 20 sccm(sccm:standard cubic centimeter per minute), dense SWCNT networks with clean surface were produced. When the flow rate was above 50 sccm, vertically aligned SWCNT(VA-SWCNT) arrays were grown. Well-aligned VA-SWCNT arrays were obtained in the temperature range of 650-800℃ and the content of large-diameter(above 1.7 nm) tubes in the array increased with the temperature. The height of the array was affected by the growth temperature, the CO flow rate, and the growth time. These findings indicate CO can be used as an efficient carbon source for the growth of SWCNTs on substrates under low flow rates.     

埃洛石纳米管模板法一步法制备一维碳纳米管/碳纳米棒混合纳米碳材料

利用埃洛石纳米管(HNTs)特有的中空纳米结构,以及丰富的界面化学性质,以聚乙烯醇(PVA)为碳源,采用浸渍填充纳米孔方法实现了一步制备一维碳纳米管(CNTs)/碳纳米棒(CNRs)混合纳米碳材料。考察模板剂(HNTs)和碳源(PVA)之间的比例关系对混合纳米碳材料的结构影响,利用XRD、FTIR、Raman、N2吸附-脱附测试、TEM、SEM以及电阻率和分散性等表征手段分析混合纳米碳材料的结构变化。结果发现,PVA填充含量的增加将导致产物中CNRs的质量分数增加;当PVA和HNTs质量之比为1∶1时,所制备的CNTs/CNRs的孔体积达到最大值2.142 cm~3·g-1,比表面积达到583 m~2·g-1,并且表现出较好的电导率和分散性,表明低的PVA填充比例制备的混合碳材料中CNTs含量较高。     

Ni/γ-Al2O3催化剂上CH4-CO2重整体系中积碳-消碳的研究

用动态热重技术和色谱技术联用以及XRD和TEM等表征手段,研究了Ni/γ-Al     

Carbon clusters

Some of the most significant discoveries and achievements concerning the mass spectra and gas phase ion chemistry of carbon clusters are reviewed. These include (1) nanosecond and femtosecond laser ionizations; (2) ion structures through ion/molecule reactions, ion chromatography, and computational methods; (3) carbon cluster cooling through radiative decay, dissociative decay, and thermionic emission; (4) mechanisms and energetics of fragmentation reactions; (5) endohedral fullerenes including recent data on ion beam implantation, and (6) ion chemistry as a function of the fullerene charge state.     

Palladium-Catalyzed Addition of Carbon Monoxide and Carbon Tetrachloride to 1-Octene in Supercritical Carbon Dioxide

The Pd-catalyzed addition of carbon monoxide and carbon tetrachloride to 1-octene gave coadduct [alkyl 2-( 2, 2, 2-trichloroethyl)octanoate] as the major product in supercritical carbon dioxide by using pyridine as the base. It was found that the selectivity and the yield of coadduct were greatly affected by the pressure of carbon dioxide, the reaction temperature and the amounts of alcohol and base used.     

碳纳米管含量对炭炭复合材料组织及力学性能的影响

炭纤维上原位合成了均匀生长且具有伸张形貌的碳纳米管,借助化学气相渗透制备了碳纳米管增强的炭炭复合材料,研究了不同含量的碳纳米管对炭炭复合材料组织和力学性能的影响。结果表明：炭纤维上生长碳纳米管改变了热解炭的沉积行为,诱导了各向同性热解炭的生成,且随着碳纳米管含量的增加,各向同性热解炭的厚度增加,但是复合材料的d002值却明显降低。微量的碳纳米管即可显著提高复合材料的力学强度,随着其含量的增加,复合材料的力学强度和模量迅速提高,但材料的断裂行为却急剧恶化,断裂模式由最初的假塑性断裂转变为脆性断裂。     

双酚A在壳聚糖-FC-134-碳纳米管修饰电极上的电化学行为及其测定

采用十二烷基硫酸钠(SDS)与全氟辛基磺酰季碘化物FC-134作为碳纳米管的复合分散剂,制备了壳聚糖-碳纳米管修饰电极(MFC/GCE)。研究了环境激素双酚A在pH 8.0磷酸盐缓冲溶液中的电化学行为,并探讨了其电极过程机理。峰电位为0.450 V,峰电流与其浓度在2.5×10-7~1.0×10-4mol/L范围内呈线性关系,检出限为1.0×10-8mol/L。该法用于环境水样中双酚A含量的测定并与荧光法对照,测定结果吻合。