球形铅-锰复合氧化物载体制备及性能评价

通过油氨柱成型法制备了球形铅-锰复合氧化物载体,并利用X射线衍射（XRD）、BET法比面积测试等技术对球状载体进行了表征。结果表明,在焙烧温度为450 ℃、活性炭添加量为2%（质量分数）条件下,制得的球状载体的性能最优。此时,载体的主要成分为氧化锰和四氧化三铅;同时,前驱体碳酸盐完全分解生成的二氧化碳气体,在逸出的过程中在载体内部形成了大量的孔道结构,使得载体的比表面积达到129.80 m2/g;同时,载体的机械抗压强度达到17.8 N,使得反应后的载体仍具有完整的球状形貌。以氯化钯溶液为钯源,利用沉淀法将球形铅-锰复合氧化物载体负载0.5%（质量分数）钯后,用于苯酚氧化羰基化合成碳酸二苯酯的催化反应,碳酸二苯酯的收率可达14.34%,选择性在99.20%以上。     

检测实验室关键消耗品供应商的评审

《检测和校准实验室能力认可准则》中针对"服务和供给品的采购"条款中对供给品的采购有明确规定。检测实验室供给品的供应商在采购过程中起到重要作用。针对检测实验室关键消耗品供应商的评审可分为供给品的产品认证和供应商评审2个部分,包括对供应商合法运行、安全生产、过程管理、质量控制、劳动保障、研发能力和售后服务等7个方面。通过对关键消耗品供应商的评审,完成供应商资质的认证,可以为后续检测实验室关键消耗品的供应链环节提供可靠的参考资料,使检测实验室在采购消耗品的过程中有据可依,实现检测实验室日常检测对关键消耗品科学、合理、有效的供给和使用。     

四川富顺页岩气藏压裂改造模式及返排工艺分析

四川页岩气藏经过近几年的探索和开发,在借鉴北美页岩气压裂技术经验基础上,已形成我国特色
的页岩气大规模水平井多级改造技术。四川富顺页岩气藏采用以速钻桥塞分级压裂技术为主导的页岩气分段压
裂改造技术,总体改造效果在整个四川页岩地区效果相对较好。文章分析了该区块压裂改造的技术特点、砂堵和
压裂后返排的工作制度,以及返排速率、压裂液破胶时间、意外关井和气液两相流动对返排的影响,为现场作业和
优化返排制度提供一定的经验和参考。     

实时监测控制系统中CRC校验结合线性插值纠错技术研究

这篇文章研究了在实时监测系统中,通过通信方式获得的数据,在不能重传的情况下,利用CRC技术和线性插值技术结合,进行检错纠错和在CRC校验基础上利用线性插值确定局部值的合理方法.     

Solubility of Dagang vacuum residue and molecular composition of the soluble fractions in different solvents

Dagang vacuum residue (DVR) was ultrasonically extracted with fifteen organic solvents, respectively, and the soluble fractions (SFs) were analyzed with GC/MS. The results show that DVR tends to dissolve in non-polar solvent and that most of GC/MS-detectable components in the SFs are saturated hydrocarbons.     

晏家河箱型桥梁桁架法施工技术

结合工程实例,本文介绍了箱型桥梁施工中,一种与传统的钢管脚手架施工方案不同的工艺——桁架方案。     

Power splitters based on the light-intensity-dependent superprism effect

By utilizing the nonlinear Kerr effect of the background medium, power splitters based on the light-intensity-dependent superprism effect are realized in a two-stage system, where two photonic lattices are rotated to each other by 16 degrees . The nonlinear finite-difference time-domain method is applied to conducting numerical experiments. The first lattice acts as the deflecting stage, in which beams with different power densities are separated from each other spatially. The second lattice has a function of "angular amplifier" that enlarges the separation angle between two power density ranges (lower than 100 W/microm2 and higher than 300 W/microm2) to 90 degrees-like. In the first photonic band, due to the local change of refractive indices induced by the pumping power, new interfaces are formed between the pumped and nonpumped areas. The k-vector will be rotated by these interfaces until the phase velocity and group velocity have the same direction. The shape of the interface between these two stages is discussed.     

Atmospheric deposition of halogenated flame retardants at urban, e-waste, and rural locations in southern China

Measurements of atmospheric deposition fluxes and temporal variation of halogenated flame retardants (HFRs) from 2007 to 2008 at urban, electronic waste (e-waste), and rural sites in southern China are presented. The deposition fluxes of total HFRs at the urban (99.3-1327 ng m(-2) day(-1)) and e-waste (79.1-1200 ng m(-2) day(-1)) sites were much higher than at the rural site (9.27-79.5 ng m(-2) day(-1)), demonstrating that e-waste recycling and industrial activities in southern China are two important sources of HFRs in the environment. The urban deposition profile was dominated by current-use HFRs (decabrominated diphenyl ether and decabromodiphenyl ethane), whereas the profile at the e-waste site reflects the past when significant amounts of PBDEs and Dechlorane Plus were used. Source apportionment estimated by principal component analyses with multiple linear regression analysis showed that deposition HFRs at the rural site were primarily contributed by the urban and e-waste sources (45% and 38%, respectively) compared to the contribution from local emission (17%). Our results suggest that the HFRs that are readily present in gas or sorbed onto fine particle phases have enhanced potential for long-range atmospheric transport.     

半制备高效液相色谱-离子色谱法检测婴幼儿配方食品中低聚半乳糖的含量

优化并建立了半制备高效液相色谱法分离和收集、离子色谱法测定婴幼儿配方食品中低聚半乳糖的方法。本实验以乳粉、特殊医学配方奶粉和液态奶为实验对象,利用半制备高效液相色谱法分别收集婴幼儿配方食品中的二糖和三糖及聚合度(Degree of polymerization,DP)3以上的糖,再利用β-半乳糖苷酶水解收集到的聚合度3及3以上的糖组分,利用离子色谱法测定酶解后的半乳糖和葡萄糖的含量,通过计算得到样品中低聚半乳糖的含量。半制备高效液相色谱馏分固定相为Ag+色谱柱(200 mm×10 mm),流动相为100%超纯水,流速0.3 mL/min,进样量100 μL,柱温80℃;离子色谱条件固定相为Carbo Pac PA-1色谱柱(250 mm×4 mm),流动相为0.5 mol/L的氢氧化钠溶液、0.5 mol/L的乙酸钠和超纯水梯度洗脱,柱温30℃,进样量25 μL。测定的异乳糖、葡萄糖、半乳糖、1,6-β-D-半乳二糖和1,3(4)-β-D-半乳二糖线性范围在1.0～30.0 μg/mL,相关系数在0.9985～0.9999,回收率在82.80%～87.67%,相对标准偏差(Relative standard deviation,RSD)≤5%。该方法结果准确,能够满足检测要求,前处理操作简单,便于大批量样品的检测。