Bamboo biochar-catalytic degradation of lignin under microwave heating

Abstract

Lignin biochar-catalytic depolymerization using biochar Fe-600, Fe-800, Ni-600, Ni-800 catalysts under microwave-heating (180?°C for 30?min) was explored in an ethanol/formic acid (1:1) media. Non-catalyst depolymerization was also studied and compared with the biochar-catalysts results. Characteristics of the bio-char catalysts were analyze by BET, XRD, and FT-IR. GPC, FT-IR, and MALDI-TOF MS spectrometry were also used to characterize the depolymerization products. The experimental results showed that the S_BET, V_t, and V_mec and average pore diameter of the biochars are considerably dependent on the preparation temperature and type of cation (Ni²⁺ or Fe³⁺). The maximum yield of bio-oil product was obtained as 85?wt% with the addition of biochar Ni-600 and the total amount of oligomers or monomers with a molecular weight of 164 to 446 reaches 80.4%.     

Comparative Study on Microstructures of Zincalume Steel (G550) Welded Joint Between Metal Inert Gas and Laser Beam Welding

Zincalume steel (G550) is commonly used in various construction fields because of its high corrosion resistance and good mechanical properties. In recent years, a number of steel companies have massively produced zincalume steel (G550) with large volumes of waste. For the reduction of massive industrial wastes, the zincalume steel (G550) was welded in the lap joint configuration using different welding parameters in the metal inert gas (MIG) welding and laser beam welding (LBW) process in this study. The MIG welding and LBW are more welcomed welding methods due to their high efficiency and low cost. However, they are different as the LBW offers welding speed three to five times faster than MIG welding, while LBW’s heat transfer to workpieces is much less than MIG welding, which can avoid some distortions. The microstructure of zincalume steel (G550) was investigated using scanning electron microscopy (SEM) and the microstructure characterizations of welded specimens were analyzed. The experiment found the columnar dendrites extended under the heat flow direction during the MIG welding and LBW process. Thus, the columnar grains were formed in between the equiaxed zone and fusion zone (FZ) at high heat input and slow cooling rate. Moreover, the grain size of FZ was comparatively smaller than heat affected zone (HAZ) and base metal (BM).     

火焰原子吸收法测定食品中铜元素含量的不确定度评定

通过火焰原子吸收光谱法测定动物源食品中铜的含量,分析测试过程中不确定度的来源,并对各不确定度的分量进行评定。分析结果显示不确定度主要来源于标准溶液测定(包括标准储备液,标准应用液的稀释,标准系列的配置,标准曲线的拟合的不确定度)、样品的称量,考核样品的稀释和重复测量样品。计算出各种不确定度分量并将其合成,以此计算食品中铜的测试结果为:CCu=(3.20±0.166)mg/kg,k=2(置信水平约为95%)。     

基于OpenOffice.org的维吾尔文办公套件的研究与实现

在分析OpenOffice.org体系结构的基础上,研究软件的国际化与本地化机制,针对维吾尔文字本地化需求进行了一系列定制与开发,形成了一套支持维吾尔文输入输出的OpenOffice.org办公套件。     

多汽源高温差分汽缸和对流式热交换器的设计

鉴于多汽源高温差大型分汽缸容易出现热疲劳现象,根据传热学和流体力学原理,对现有的分汽缸结构进行改进,让高低温蒸汽在筒体内的空间通过对流的方式完成热交换,避免了热疲劳的出现。该型号设备已经在工程上使用,并且运转正常。通过分析这种分汽缸的工作原理,发现它已经实现分汽和换热两个作用,根据这个启示,进一步设计出对流式换热器,对流式换热器和传统的换热器比较有非常多的优点,应用范围很广,本文给出三种结构供参考。     

煤层注水在艾维尔沟焦煤公司煤矿中的应用

煤层注水是在回采前,通过钻孔,将压力水注入煤体,通过预湿煤体,以改变煤的物理力学性质,减小回采过程中的产尘量,对改善井下员工工作条件具有重要的意义.新疆焦煤集团艾维尔沟焦煤公司煤矿开采的6<'#>煤层进行的注水试验,通过合理选择煤层注水钻孔施工工艺、优化煤层注水参数、煤的孔隙率鉴定,减少了影响煤层注水效果的因素,提高煤层注水效果,为该公司煤矿综采降尘提供了参考依据.     

新疆自然旅游资源成因类型划分研究及其对新疆旅游业发展的意义

作者在深入研究新疆自然旅游资源的基础上，对新疆自然旅游资源成因类型进行了划分，并对开发利用新疆自然旅游资源提出了建议．     

新、旧活性干酵母质量鉴定及在葡萄酒中的应用

按地业标准方法,我们对国内外５个品牌活性干酵母的活细胞率,含水量和发酵力等质量标准进行了连续两年的检测,发现旧活性干酵母的各项质量指标均有所下砦使用旧活性干酵母时,应区别对待。     

不同温度、澄清剂对美乐葡萄酒澄清效果的研究

通过研究不同温度、澄清剂对美乐葡萄酒的澄清度的影响,结果表明：低温能够提高葡萄酒的澄清效果和速度,而且随着温度的降低、单宁、色度和干浸出物有减少的趋势。