小合成氨碳丙脱碳系统的清洗

我国采用碳酸丙烯脂脱除变换气中二氧化碳的小合成氨装置中,脱碳系统的主要设备内极易沉积硫垢,这种结垢是由碳丙工艺所决定,因而不可避免．硫垢影响设备的运行,但由于硫垢与水垢性能相差极大,通常的机械清洗与化学清洗很难奏效．通过５ 套小合成氨碳丙脱碳设备的清洗证明：ＨＦ－ ００２ 络合清洗法是这类硫垢的有效清除方法．     

青海混合原油综合评价Ⅰ.常规评价

对青海混合原油进行了综合评价,分析了原油和各个馏分的性质。结果表明,该混合原油的相对密度指数大、凝固点高、含蜡量多、特性因数大、硫含量低,系低硫石蜡基原油。实沸点蒸馏及窄馏分性质分析表明,该混合原油初馏点〈30℃,初馏点至200℃直馏汽油收率13．91％,140℃～240℃喷气燃料馏分收率10．61％,200℃～300℃轻柴油馏分收率14．39％,300℃～350℃柴油馏分收率10．83％,350℃前馏分收率合计39．13％,中性油原料占原油42．33％,500℃前馏分总拔出率70．63％,且混合原油灰分含量低,重金属含量不高,氮含量较低,适宜生产燃料和润滑油型炼厂加工。     

蘑菇保鲜剂的筛选及其保鲜效果

以L-半胱氨酸等作为护色剂,进行蘑菇保鲜研究。经正交试验,筛选出最佳保鲜剂配方为:L-半胱氨酸(L-Cys)、柠檬酸(CA)、植酸(PA)和乙二胺四乙酸二钠(EDTA-2Na)浓度分别为2.5 mg/mL、9.0 mg/mL、1.5 mg/mL和 0.5 mg/mL。蘑菇用此复合保鲜剂在(5±1)℃下可保存12 d,其效果好于单一保鲜剂(L-Cys)和对照,贮藏期间不开伞,色泽乳白,无褐变,气味正常,蘑菇褐变度、电导率和呼吸强度等指标明显低于L-Cys和对照,鲜度指数则高于L-Cys和对照。     

Effect of Strength and Microstructure on Stress Corrosion Cracking Behavior and Mechanism of X80 Pipeline Steel in High pH Carbonate/Bicarbonate Solution

The stress corrosion cracking (SCC) behaviors and mechanisms of X80 pipeline steels with different strength and microstructure in high pH carbonate/bicarbonate solution were investigated by slow strain rate testing and electrochemical test. The results showed that the cracking mode of low strength X80 steel composed of bulky polygonal ferrite and granular bainite in high pH solution was intergranular (IGSCC), and the SCC mechanism was anodic dissolution (AD). While the mixed cracking mode of high strength X80 steel consisted of fine acicular ferrite and granular bainite was intergranular (IGSCC) in the early stage, and transgranular (TGSCC) in the later stage. The decrease of pH value of crack tip was probably the key reason for the occurrence of TGSCC. The SCC mechanism may be a mixed mode of AD and hydrogen embrittlement (HE), and the HE mechanism may play a significant role in the deep crack propagation at the later stage. The cracking modes and SCC mechanisms of the two X80 steels were associated with its microstructure and strength.     

新型锤式粉碎机的使用及效果

我厂是一个轮窑一次码烧的烧结砖生产厂,年产砖3000万块.生产原料为含粘土较多的页岩,原料中既有软土又有较坚硬的岩石.由于本厂地处四川,雨水较多,原料含水量较大,一般水分含量为10%～15%.选择粉碎设备时我们最初想选择周围砖厂采用的方法：即原料粉碎后需经过筛的粉碎机,后经协会推荐,我们选择了不经粉碎把原料送入机中粉碎,粉碎后也不经筛分即可直接用于做砖的新型锤式粉碎机.因为这种设备布置简单,投资也不高,使用设备少,电耗也省,占用场地不大,工艺布置简单.     

Investigation of nanostructure of konjac-based water absorbents with atomic force microscopy

Atomic force microscopy technology is gradually spreading to almost all aspects, including food science and technology, since it was first invented in 1986. In this study, this powerful instrument was applied to image nanostructures of three water absorbents-original konjac powder, konjac powder grafted with acrylic acid using ⁶⁰Co γ-irradiation and regenerated grafted powder. Water absorption capacities and the rates of the three absorbents were also determined in this work. Original konjac powder could only absorb 60 times (w/w) of water, while 270 times for the grafted absorbent and 360 times for the regenerated absorbent. The initial water absorption rates in both tap and distilled water were high, but the rate decreased steeply as time elapsed. After 20 min, the absorbent was close to saturated status. These physical properties were in accordance with the nanostructures of these three water absorbents.     

Sol–gel-template synthesis of ZnO nanotubes and its coaxial nanocomposites of LiMn2O4/ZnO

The coaxial nanostructure composite materials of LiMn₂O₄ nanowires encapsulated in ZnO nanotubes are fabricated successfully via sol–gel method by using two-step template process. Transmission electron microscopy (TEM) and scanning electronic microscopy (SEM) results conformably show that the synthesized ZnO nanotubes possess the explicit end-opened tubular structure in uniform out diameter and wall thickness. Selected area electron diffraction (SAED) pattern, X-ray diffractometer (XRD), and X-ray photoelectron spectroscope (XPS) analysis jointly demonstrate that the main body of the fabricated coaxial composites is spinel structure LiMn₂O₄. It is expected that the two-step template process can be used to mass-produce coaxial LiMn₂O₄/ZnO nanocomposite materials as a novel cathode materials in lithium ion battery.     

Y-130／39-2锅炉负荷不足原因分析

某石化厂1^#锅炉(Y-130／39-2)长期处于低负荷运行．根据现场测试数据,分析了其负荷不足的原因,提出了改进意见．实践证明．提出的措施是可行的．     

An investigation of the friction and wear behaviors of polyphenylene sulfide filled with solid lubricants

Composites of polyphenylene sulfide (PPS) filled with solid lubricant particles of graphite (C), molybdenum disulfide (MoS₂), and polytetrafluoroethylene (PTFE) were prepared by compression molding. The size of the solid lubricant particles was 3‐;5 µm. The friction and wear behaviors of the composites were examined with a pinon‐disk test rig. The worn composite pin surfaces and the transfer films formed on the counterface were analyzed with scanning electron microscopy. An X‐ray photo‐electron spectroscope (XPS) was used to characterize the chemical states of the elements in the transfer film. It has been found that graphite and PTFE as the fillers increase the wear resistance of PPS considerably, while MoS₂ as the filler decreases the wear resistance of PPS greatly. The fillers promote the decomposition of PPS and generate compounds, which accounts for the changes in the wear resistance of the composites.     

基于单向哈希链和多重证书的网格安全方案

本文分析了网格安全基础设施（Grid Security Infrastructure、GSI）中传统的证书撤销机制存在的问题,并提出了一种新的联合证书撤销方案。该方案使用单向哈希链和多重证书来改进证书撤销机制,CA的部分功能被分散到其它网格节点,避免了网格环境下的拥塞和单点失败。不同CA颁发的证书能够进行交叉认证,用户可以验证证书的有效性而无需从该证书的颁发CA重新获得撤销信息。因此该方案可以保证证书撤销的实时性。为了研究方案性能,和其他三种传统的证书撤销方案进行了对比实验。结果表明,相对传统的证书撤销机制本文所提出的联合证书撤销方案能使峰值请求率降低、峰值带宽变窄、安全风险降低．