乙酰化稻草/聚己内酯接枝共聚物的合成及表征

以稻草秸秆为原料,经粉碎后进行全植物秸秆的乙酰化改性,再用此乙酰化稻草同ε-己内酯(ε-CL)接枝共聚合成乙酰化稻草/聚己内酯接枝共聚物(ACSW-g-PCL)。研究了反应时间、反应温度、及单体用量对接枝率(G%)的影响。在反应温度140℃,反应时间10h,ε-CL对乙酰化稻草的质量比2:1时获得的接枝率最大为39%。产物的结构和性能通过红外光谱、核磁共振、扫描电镜、X-射线衍射和热分析仪表征,结果表明乙酰化稻草秸秆已成功接枝上聚己内酯(PCL)链段,经接枝ε-CL改性后的ACSW-g-PCL热稳定性有所改善,并具有了一定的热塑性。     

火试金法配料过程自动化的探索和应用

火试金法中配料方式采用的是传统的人工配料,针对人工配料方式的不足,设计了一款自动化程度较高的自动配料机,通过对配料机的准确性、效率及可靠性实验,结果表明配料机检测称量误差在±0.2 g以内,效率为人工配料的2~3倍,检测结果与人工配料的相一致。与此同时,应用此设备改善了工作环境,避免了人为失误造成的检测质量问题,降低了复检率,为企业降低了成本,提高了效益,在业内具有广泛应用前景。     

三醋酸甘油酯的气相色谱分析

本文介绍了一种快速、简便的测定高含量三醋酸甘油酯的气相色谱法。本法使用10%PEG-20M涂渍在Chromosob W上的色谱柱(2 m×3 mmi.d.),以N_2作载气(40ml/min)氢火焰离子化检测器(FID),柱温180℃,汽化温度200℃,能很好地将三醋酸甘油酯与二醋酸甘油酯分离。并选用十二醇为内标物测定了十批合成样品中的三醋酸甘油酯含量,变异系数<0.4%。     

悬浮液进样石墨炉原子吸收测定钒钛磁铁矿中痕量镍

样品粒度不超过３８μｍ，以２０％乙醇－１％硝酸水溶液为介质，用与样品基体类似的一种标准矿样进行校正，可消除基体效应。样品浓度不超过７３ｍｇ／１０ｍｌ，含镍０－３５０ｎｇ．ｍｌ＾－１范围内呈良好线性关系。     

In situ scanning FTIR microscopy and IR imaging of Pt electrode surface towards CO adsorption

In situ scanning FTIR microscopy was built up for the first time in the present work, which consists of an FTIR apparatus, an IR microscope, an X-Y mapping stage, and the specially designed electrochemical IR cell and computer software. It has been demonstrated that this new space-resolvd in situ IR technique can be used to study vibration properties of micro-area, and to perform IR imaging of electrode surface. The chemical image obtained using this technique fur CO adsorption on Pt electrode illustrated, at a space-resolution of 10~(-2) cm, the inhomogeneity and the distribution of reactivity of micro-area of electrode surface.     

Selective water sorbents for multiple applications, 8. sorption properties of CaCl2?SiO2 sol-gel composites

This paper presents sorption properties of CaCl₂/SiO₂ composites synthesized by a sol-gel approach. Desorption isobars measured at T=30–140°C and vapor pressure 12.8–81.0 mbar clearly show a correlation between the sorbents pore structure and their sorption properties. The sample adsorptivities are found to exceed 1.2 kg H₂O/kg adsorbent (or 20–25 mol H₂O/mol of the salt). That is markedly higher than any reported before for silica-based materials. This results in a high energy storage capacity reaching 3,400 kJ/kg of dry sorbent, as confirmed by direct calorimetric measurements. The isosteric desorption heat is found to decrease from 67±5 kJ/mol to 46±5 kJ/mol with increase in the surface coverage.     

草一光可湿性粉剂活性成分的反相高效液相色谱分析

采用反相高效液相色谱法同时测定15.5％草一光可湿性粉剂中的异丙甲草胶和苄嘧黄隆两种活性成分,以V（甲醇）：V（酸性水）=70：30作为流动相,采用ZORBAXSB-C18色谱柱。方法回收率达98.1％～102.6％,变异系数为0.4％～0.8％。     

The Crystallisation Kinetics of Nitrate Cancrinite Na7.6[AlSiO4]6(NO3)1.6 (H2O)2 Under Low Temperature Hydrothermal Conditions

Investigations on the formation of nitrate enclathrated cancrinite were performed under low temperature hydrothermal conditions (353 K, autogeneous pressure). The alkaline transformation of kaolinite in the presence of sodium nitrate was selected as the preferred method of synthesis. All experiments were carried out at high alkalinity, using a 16 molar NaOH solution as well as at low NaOH concentrations (2 molar NaOH). Qualitative phase analysis was performed by X-ray-powder diffraction and IR-spectroscopy. Besides cancrinite formation no further intermediate phases were formed. Quantitative data of the educt conversion into cancrinite was determined by ²⁷Al MAS NMR spectroscopy and integration of the resonance signals of four- and six-coordinated aluminium. Whereas full conversion could be found already after 24 h of reaction under highly alkaline conditions, only an insufficient progress of the reaction resulted in the case of low alkalinity.     

Sonochemical Preparation of Micro- and Nanometer Cu2O

Cu2O particles with different morphologies and scales were prepared sonochemically on the solid-liquid interface of CuCl and water, by adjusting the reaction factors. The products were characterized by powder X-ray diffraction（XRD） and scanning electron microscopy（SEM）. The formation and morphology of Cu2O crystals were influenced by high-intensity ultrasound, reaction temperature, and addition of CuCl. The results indicate that micrometer Cu2O was crystallized in cubic and octahedral shapes, whereas, nanometer Cu2O was not produced in well-shaped crystals.