从拜耳液中清除碳酸钠的新方法

引言碳酸钠在拜耳液中积累是所有拜耳法氧化铝厂的一个共同问题。用苛性碱液从铝土矿中溶出三水或一水铝石或者它们二者是不希望有碳酸钠的,因为它在溶出过程中是不参于反应的。碳酸钠通常用下述方法清除:     

Al及Al-Mg合金的热加工和随后的静态再结晶

引言在金属热轧中,各道次之间的静态回复,对下一道次的行为有重大影响。多道次轧制时,金属温度是逐渐降低的。这样,当间隔时间接近时,温降和前一个道次一样。这种情况完全不同于冷加工达到某一变形程度后并于不同温度下退火的情况。热加工时,高温保证了象退火时一样高的热激活,导致低的应变能。与常规变形后的纯金属相比,添加溶质,一般能降     

爆炸粉末冶金 第一部分

爆炸粉末冶金作为一种难熔金属和超合金潜在的加工技术,本文作了介绍。这些材料的难加工性向加工工业提出了挑战。本文介绍了一种球形爆炸压制装置,以期概括地描述一下工业生产所需的参数,并得出与圆柱形爆炸压制方法的相互关系。     

对高速钢切削刀具钛基陶瓷涂层的评价

用直流等离子辅助电子束物理气相沉积和射频磁控溅射在高速钢刀具上沉积钛基陶瓷涂层（包括Ti（B、N）和（Ti、A1）N）。按照国际标准方法ISO3685～1977进行纵向车削试验。切削液是有良好冷却性能的乳化液。用渗碳钢（MoCN206）和铝合金工件进行了钻削和车削试验，并用含极压添加剂的切削液进行了试验。切削试验中的参考材料是无涂层和TiN涂层高速钢刀片。     

铸造车间铝熔体的除气和净化

本文首先介绍铝熔体除气的一般方法，接着详细论述了旋转除气方法和各种旋转器的除气效果。含氢量采用熔体试样在真空中凝固的方法测量。利用所得到的铝合金的可比较气孔率，能测量出温度和时间对除气效果的影响。气孔率随旋转除气处理的时间增长呈指数下降，每隔１．５分钟下降一半。因此，能够控制除气量。本文最后对旋转除气处理的成本做了分析。     

The fate of 14C-radiolabelled diclofenac and 4'-hydroxydiclofenac in membrane bioreactor treatment of wastewater

This study aimed at enhancing knowledge on the fate of diclofenac (DF), together with its main human metabolite 4'-hydroxydiclofenac (4'OHDF), during wastewater treatment by using a laboratory-scale membrane bioreactor (MBR). The reactor was fed continuously with non-radiolabelled diclofenac for a one month period prior to a single pulse of a 14C-radiolabelled solution of DF and 4'OHDF. The solution spike contained approximately 25% 4'OHDF and 65% DF, which corresponds to the ratio observed in municipal sewage, as well as traces of two other metabolites. The radioactivity was monitored for a total of twelve days in the various output streams. The calculation of the complete mass balance in the system demonstrated that the major part of the radioactivity left the reactor with the permeate (88.7%), while 2.1% was recovered in the excess sludge. Negligible amounts were recovered in the off-gas traps and on the membranes. Chromatographic analyses of effluent samples, by means of HPLC-MS coupled in parallel to a radiodetector, displayed a different pattern than the one of the spiked solution. It showed the occurrence of three additional metabolites.     

奥林匹斯神话最终章——小记《战神III》当中的奥林匹斯众神

次时代主机上的第一作《战神》,无论是人物刻画、场景表现以及关卡设计上都下足了功夫。游戏当中出场的每一个人物,其背后都有一个相当庞大的希腊神话背景作为支撑,而这些或悲或喜的故事,也正是我们理解《战神III》各个经典场面的基石。     

第一既出 谁与争锋 细数游戏之“最”

游戏的世界里总会带给我们各式各样的挑战和惊喜,也在不断地突破自我、创造传奇。纵览当今的游戏世界,其中有多少的“第一”你能脱口而出呢？或许只是一个数据,或许只是一张图片,或许只是一分钟,就创造了又一项巅峰记录。去年,我们曾经刊登过美国游戏媒体评出的“游戏吉尼斯记录”;最近,日本媒体又公布了一系列游戏之“最”。这些游戏世界里的“第一”都包括哪些令人瞩目的焦点,我们就一同来看看。     

A scalable kernel-based semisupervised metric learning algorithm with out-of-sample generalization ability

In recent years, metric learning in the semisupervised setting has aroused a lot of research interest. One type of semisupervised metric learning utilizes supervisory information in the form of pairwise similarity or dissimilarity constraints. However, most methods proposed so far are either limited to linear metric learning or unable to scale well with the data set size. In this letter, we propose a nonlinear metric learning method based on the kernel approach. By applying low-rank approximation to the kernel matrix, our method can handle significantly larger data sets. Moreover, our low-rank approximation scheme can naturally lead to out-of-sample generalization. Experiments performed on both artificial and real-world data show very promising results.     

Fabrication of patterned single-walled carbon nanotube films using electrophoretic deposition

Thin films of chemically functionalized single-walled carbon nanotubes (SWNTs) were fabricated by using a direct current (dc) electrophoretic deposition method. SWNTs were shortened and then functionalized with acid chloride group to combine with the amine group-terminated gold substrate. Silica nanospheres with a diameter of about 190nm were arrayed on gold substrate to pattern a thin SWNT film. Periodically patterned SWNT film was eventually produced and would be used in potential applications like electron emitters and large surface area electrodes.