Facile Synthesis of 2PbCO3·Pb(OH)2 Microcrystals and Its Catalytic Behavior for Transesterification of Dimethyl Carbonate with Phenol

Polyhedron lead hydroxide carbonate （2PbCO3·Pb（OH）2 ） microcrystals have been prepared in solution phase via a facile method in the presence of surfactant cetyltrimethylammonium bromide （CTAB）. All the samples were characterized by powder X-ray diffraction ,pattern （XRD）, field-emission scanning electron mi- croscopy （FE-SEM）, high-resolution transmission electron microscopy （HRTEM）, and selected area electron diffraction （SAED）. The possible growth mechanism was discussed. 2PbCO3·Pb（OH）2 microcrystals were found to be a novel and efficient catalyst for the synthesis of diphenyl carbonate （DPC） by transesterification of dimethyl carbonate （DMC） with phenol. Compared with some other catalysts, such as AlCl3, ZnCl2, and Mg5（CO3）4（OH）2, 2PbCO3·Pb（OH）2 microcrystals are stable and show relatively high activity at low catalyst amount. When the reaction was carried out at 180 12, with a molar ratio of phenol to DMC of 2：1, a reaction time 14 h, and a catalyst amount 0.2% （molar ratio to phenol）, the selectivity of DPC and methyl phenyl carbonate （MPC） was 14.7% and 78.8%, respectively.     

适合于脆性材料受拉性能试验的试验机辅助吸能装置

为测定混凝土、石料等脆性材料的抗拉应力应变关系全过程曲线，作者在普通材料试验机上研制了一种采用薄壁金属套筒及球铰方式对中的受拉辅助吸能装置。通过对高强混凝土试件的实测表明，该装置能减少轴拉过程中偏心的影响，有效地吸收在试件破坏瞬间试验机所释放的弹性变形能，延缓试件的破坏过程，不失为一种解决问题的新途径。     

微机并行口实现高精度数据采集的研究

以模数转换器 Ｍ Ａ Ｘ１３５ 与便携式微机接口为例,介绍了微机通过并口与 Ａ／ Ｄ 芯片进行接口从而实现高精度数据采集的方法,突破了传统微机数据采集系统中 Ａ／ Ｄ 芯片必须直接与微处理器接口或者直接与微机总线接口的局限．     

多探头 K 分割编码结构及循环码编码器研究

针对增量型数字编码器提出了一种多探头Ｋ分割编码结构及与之相应的一种增量型循环码编码器的基本结构，并研究了这种Ｋ分割方式下编码状态的特征及规律，确立了一种以二进制循环码为特征标志的编码方式．尤其是这种基于Ｋ分割编码结构原理的循环码编码器，在改进码盘结构及提高编码器综合性能方面具有显著的效果．     

多探头K分割编码结构及循环码编码器研究

针对增量型数字编码器提出了一种多探头Ｋ分割编码结构及与之相应的一种增量型循环码编码器的基本结构，并研究了这种Ｋ分割方式下编码状态的特征及规律，确立了一种以二进制循环码为特征标志的编码方式。尤其是这种基于Ｋ分割编码结构原理的循环码编码器，在改进码盘结构及提高编码器综合性能方面具有显著的效果。     

纳米Fe3O4固载聚苯乙烯球对甲烷水合物生成与分解的影响

为了提高甲烷水合物合成反应中的传热效率,选取纳米Fe_3O_4作为导热材料,将不同量的纳米Fe_3O_4固载在聚苯乙烯球(PSNS)上,通过乳液聚合法制备了20%Fe_3O_4/PSNS和40%Fe_3O_4/PSNS两种新型聚苯乙烯球,并研究了PSNS,20%Fe_3O_4/PSNS,40%Fe_3O_4/PSNS三种聚苯乙烯溶液和十二烷基硫酸钠(SDS)对甲烷水合物生成与分解的影响。实验结果表明:三种聚苯乙烯溶液生成的水合物储气倍数和分解后甲烷回收率均高于SDS的100V/V,72.50%;对比三种聚苯乙烯溶液的促进效果发现,Fe_3O_4的存在明显缩短了水合物反应平衡时间,随着Fe_3O_4含量的增加,反应平衡时间由18 h缩短到9 h;Fe_3O_4提高了甲烷回收率,以20%Fe_3O_4/PSNS和40%Fe_3O_4/PSNS为促进剂时,水合物分解后甲烷回收率分别为92.15%,89.80%,都高于PSNS的85.00%。     

一种新型的增量式序位码编码器

提出了一种多探头k分割编码结构原理及一种新型的增量式序位码编码器结构，可有效地增加码盘容量．提高分辨率并减少码道标志数，可缩小码盘尺寸．     

等效荷载在静定单跨梁试验中的应用

主要介绍静定单跨梁试验中等效荷载的换算和使用，并将计算结果列成表格．     

A system combining microbial fuel cell with photobioreactor for continuous domestic wastewater treatment and bioelectricity generation

A coupled system consisting of an upflow membrane-less microbial fuel cell (upflow ML-MFC) and a photobioreactor was developed, and its effectiveness for continuous wastewater treatment and electricity production was evaluated. Wastewater was fed to the upflow ML-MFC to remove chemical oxygen demand (COD), phosphorus and nitrogen with simultaneous electricity generation. The effluent from the cathode compartment of the upflow ML-MFC was then continuously fed to an external photobioreactor for removing the remaining phosphorus and nitrogen using microalgae. Alone, the upflow ML-MFC produces a maximum power density of 481 mW/m 3 , and obtains 77.9% COD, 23.5% total phosphorus (TP) and 97.6% NH4+-N removals. When combined with the photobioreactor, the system achieves 99.3% TP and 99.0% NH4+-N total removal. These results show both the effectiveness and the potential application of the coupled system to continuously treat domestic wastewater and simultaneously generate electricity and biomass.