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报道了亚硝酸化学诱变原理、对一株优势氧化铁硫杆菌T .f菌的诱变作用和诱变T .f菌对低品位黄铜矿的生物浸出研究结果。结果表明 ,T .f菌亚硝酸化学诱变后 ,诱变T .f菌和原始T .f菌相比 ,活性提高了 41.0 3 % ,对黄铜矿的浸出率提高了 13 .3 % ,达到浸出终点的时间比原始菌减少了 5~ 10d。诱变后的T .f菌对黄铜矿比原始T .f菌具有更好的浸出效果 相似文献
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Ministry of Industry and Information Technology Published "Directory of Process,Technology and Equipment for Industrial Water Saving Encouraged by the State(First Edition)"(Draft) 下载免费PDF全文
《造纸信息》2014,(8):76-77
On December 25th, 2013, the Ministry of Industry and Information Technology published "Directory of Process Technology and Equipment for Industrial Water Saving Encouraged by the State (First Edition)" (Draft) on its website. 相似文献
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Investigation of chemi‐crystallization and free volume changes of high‐density polyethylene weathered in a subtropical humid zone 下载免费PDF全文
Jian Xiong Kai Ni Xia Liao Jingjun Zhu Zhu An Qi Yang Yajiang Huang Guangxian Li 《Polymer International》2016,65(12):1474-1481
The chemi‐crystallization and free volume changes of high‐density polyethylene (HDPE) exposed to subtropical humid climate of Guangzhou, China, were investigated using Fourier transform infrared spectroscopy, differential scanning calorimetry, wide‐angle X‐ray diffraction, dynamic mechanical analysis and positron annihilation lifetime spectroscopy. An increase in content of carbonyl groups and significant chemi‐crystallization were observed to occur during natural exposure. Chain scission accounted for the chemi‐crystallization and would lead to greater crystallizability of the molecules. The reheating DSC run indicated that the crystallizability of the degraded HDPE molecules increased initially with exposure time and then decreased. Positron data showed the new crystals induced by chemi‐crystallization indeed had more imperfect crystal structure in comparison with the pre‐existing parent crystals, and the free volume located in amorphous regions decreased involving a shrinking of the free volume holes. The shrinkage of free volume holes was correlated with the loss of mobility of HDPE molecules, which was confirmed by the increase of glass transition temperature. The formation of new imperfect crystals might increase the amount of rigid amorphous fraction of HDPE materials, as well as the occurrence of crosslinking reactions of molecules located in the interior of HDPE materials, consequently decreasing the molecular mobility. © 2016 Society of Chemical Industry 相似文献
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研究了20 kHz的圆柱形料腔中超声空化效应的形成及其空间分布特性。应用柱贝塞尔函数,推导获取了柱形声场内超声传播的声能密度的分布,并采用有限元方法进行仿真分析。针对频率为20 kHz的功率超声实验,结合声学测量方法和鲁米诺声致化学发光方法,对理论分析结果进行了验证对照。结果表明:料腔半径R=50 mm,20 kHz谐振液位高度H=90 mm时,若功放电流<40 mA,超声空化效应出现在变幅杆端部区域;若40 mA≤功放电流≤80 mA,空化效应显著增强,空化效应的空间分布与场内声压分布一致,空化效应受声模态影响,形成远场空化效应的分布特性;若功放电流>80 mA,受非线性因素影响,谐振液位时,空化效应在声流作用下呈柱形拖尾状分布,并在底部壁面边界形成平铺状分布;非谐振液位高度等于75 mm时,超声空化效应随功率增加仅在变幅杆端部区域出现,且呈现局域空化分布特性。 相似文献
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为解决辽宁省造纸用材 ,合理开发利用现有的以柞木和水曲柳为主的硬杂木资源 ,对辽宁省东部山区次生林中的主要材种———柞木做了制取磺化化机浆 (SCMP)的研究。研究结果表明 ,对磺化影响的显著程度是亚硫酸钠用量 >磺化温度 >磺化时间。由此确定实验的最佳条件为Na2 SO3 用量 30 % (对绝干木片 )、最高温度 16 0℃、保温时间 70min ,在此条件下所得磺化化机浆的得率为 80 .4% ,白度为 32 .5 %SBD ,磺化度为 0 .95 %。成浆打浆度为 14°SR时与同等打浆度的苛性钠法半化学浆的强度相当 ,而浆得率和白度分别高出 7%和 2 0 %。因此以柞木为原料用SCMP制浆方法取代苛性钠法半化学浆是可行的。 相似文献
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文中介绍了增强化学发光的工作机理.针对发光物的特性,对光电倍增管(PMT)光子计数系统供电电路及其前置放大器设计做了阐述.用C14系列做微弱光源进行了实验,结果表明,此系统设计线性动态范围很宽,噪声小,能有效应用于类似的光子计数检测分析仪器. 相似文献
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