矿物/IFR复合阻燃剂对UPR阻燃、抑烟性能的影响

将一种矿物与膨胀型阻燃剂(1FR,聚磷酸铵/季戊四醇/三聚氰胺,APP/PER/Mel)复配,应用于不饱和聚酯树脂(UPR),得到膨胀型阻燃UPR复合材料。通过氧指数(LOI)、垂直燃烧(UL94)、烟密度等级(SDR)、DSC-TG对复合阻燃材料的阻燃、抑烟及热稳定性能进行研究。结果表明,在该膨胀型复合阻燃剂中,矿物与IFR存在明显的协效作用,在矿物:APP:PER:Mel=4:2:1:1(质量比),(复合阻燃剂)=40%的情况下,LOI高达36.4%,阻燃级别为UL94V-0级,SDR为60.84,满足国家对Bl级电器类热固性塑料的使用要求。     

离子液体中FCC模拟汽油相转移催化氧化脱硫研究

合成了一种磷钨杂多酸季铵盐[CTMA]3PW12O40,以此为相转移催化剂,离子液体[Omim]PF6为萃取剂,构建了[CTMA]3PW12O40/[Omim]PF6/H2O2催化氧化萃取耦合脱硫体系,用于脱除FCC模拟汽油中二苯并噻吩(DBT)。考察了双氧水用量、反应温度、反应时间和催化剂用量对DBT脱除效果的影响,结果表明:当双氧水用量n(H2O2)/n(S)=4、反应温度T=60℃、反应时间t=90min、催化剂用量n(催化剂)/n(S)=1∶10、萃取剂[Omim]PF6用量为1mL时,该脱硫体系中DBT脱除率可达96.9%。     

磷钼杂多酸钝化工艺研究

铬酸盐钝化是常用的钝化处理方法,其钝化液中的Cr6 对人体及环境都有严重危害,为了替代铬酸盐钝化处理液,采用磷钼杂多酸为主要成分的钝化液对镀锌板进行钝化处理.通过中性盐雾(NSS)试验、湿热试验、盐水浸泡试验,确定了磷钼杂多酸钝化工艺及其相关参数.结果表明,本工艺简单、成本较低,镀锌板采用磷钼杂多酸钝化液处理后,耐蚀性明显提高,在质量分数为5%的NaCl溶液中浸泡54h无白锈生成.     

具有染料选择性吸附的杂多酸季铵盐制备与性能研究

目的:制备磷钼钒杂多酸季铵盐,并且在模拟废水中对亚甲基蓝和甲基橙染料的吸附性能进行探索。方法:采用多种不同比的钼酸钠、磷酸氢二钠、偏钒酸钠和四丁基溴化铵的溶液,通过红外光谱、XRD、氮气吸脱附、SEM等对杂多酸季铵盐进行表征和结构分析。结果:制备得三种磷钼钒杂多酸季铵盐。结论:三种杂多酸季铵盐(C_(16)H_(36)BrN-PMo_5V_(10)(PMo_5V_(10)),C_(16)H_(36)BrN-PMo_9V_(3.2)(PMo_9V_(3.2))和C_(16)H_(36)BrN-PMo_(11)V_1(PMo_(11)V_1))对亚甲基蓝的吸附量分别为19.326 8、117.302 6和14.487 7 mg·g~(-1),PMo_9V_(3.2)具有优秀的亚甲基蓝选择性吸附效果。     

磷钼酸铵在半硬质聚氯乙烯中阻燃-抑烟的应用

采用化学沉淀法制备磷钼酸铵(APM),并使用红外光谱与X射线衍射仪对其进行检测,结果表明,获得了磷钼酸铵,且其中含有结晶水与少量(NH4)_3PO_4(MoO_3)_(12)·4H_2O。将制备的磷钼酸铵与三氧化钼(MoO_3)、八钼酸铵(AOM)对半硬质聚氯乙烯(PVC)的抑烟性能、阻燃性能及热稳定性能进行对比,并分别通过烟密度、锥形量热及热失重分析表征,结果表明,PVC/APM的抑烟性能、阻燃性能及热稳定性能比PVC空白样、PVC/MoO_3及PVC/AOM更优异,使半硬质PVC的最大烟密度(MSD)与烟密度等级(SDR)分别降低至78.47与61.82;总释放热(THR)降低21.98%;添加5 phr APM后,半硬质PVC在700℃时的残炭量提升21.61%。     

钛铁矿、还原钛中磷的测定——碱熔磷钼兰比色法

一、方法提要试样碱熔后,以1︰1盐酸提取,分取试液在酸性溶液中,PO4-3与MOO4-2生成黄色的磷钼杂多酸,磷钼酸被还原后呈蓝色,在波长680毫微米处进行比色。本方法使用范围:适用于磷含量0.005～-0.08%。     

阻燃型聚氨酯丙烯酸酯UV固化胶黏剂的制备与表征

分别通过接枝共聚的方法在预聚物聚氨酯丙烯酸酯(PUA)分子结构中引入P、N阻燃元素,探讨合成含磷枝化和含磷骨架聚氨酯丙烯酸酯的影响因素,并对其制备的UV固化胶黏剂的力学性能、阻燃性和热稳定性进行了研究。结果表明,当n(HMDI)∶n(PDEGA3000)∶n(FRC-2)∶n(HEA)=2.3∶1∶1∶1,w(DBTDL)=0.3%,w(MEHQ)=0.3%,w(HDDA)=20%时,合成了■达7200和PDI为1.53的预聚物P-PUA_1;当n(HMDI)∶n(FRC-6)∶n(HEA)=2.05∶1∶2,w(DBTDL)=0.45%,w(MEHQ)=0.3%,w(HDDA)=20%时,合成了■达1800,PDI为1.02的预聚物P-PUA_2;当m(PUA)∶m(P-PUA_1)∶m(P-PUA_2)=1∶1∶1,w(Irgacure1173)=3%,w(二甲基苯胺)=2%,w(HDDA)=25%时,可得到黏度6900 mPa·s、剪切强度8.19 MPa、硬度57 HD、LOI 25%、阻燃等级UL94V-2和热稳定性优异的UV固化胶黏剂。     

海泡石的剥离改性及阻燃不饱和聚酯

为获得低烟无卤阻燃不饱和聚酯(UPR),采用将改性海泡石与膨胀型阻燃剂复配的方式对UPR进行阻燃性能研究.通过酸热处理和离子交换改性法获得了剥离效果良好的有机化改性海泡石纤维,通过扫描电镜、X射线衍射、傅里叶红外光谱等测试方法对改性海泡石的表观形貌、剥离效果及其UPR中的分散效果进行了表征.将改性海泡石与聚磷酸铵(APP)、季戊四醇(PER)等膨胀型阻燃剂进行复配添加到UPR中,极限氧指数(LOI)测试和烟密度(SDR)测试结果表明,所制得的海泡石/不饱和聚酯复合材料具有较好的阻燃、抑烟性能.     

离子液体中杂多酸季铵盐催化氧化汽油脱硫研究

将二苯并噻吩(DBT)溶于正辛烷配制成模拟汽油(硫含量500μg/g),以磷钼钒杂多酸季铵盐[(CH3)4N]4PMo11VO40为催化剂,离子液体[BMIM]PF6为萃取剂,H2O2为氧化剂,考察了催化剂用量、双氧水用量、反应温度、反应时间和硫化物种类对模拟汽油脱硫率的影响,并探讨了催化氧化脱硫机理。结果表明:当催化剂用量为0.02g/mL油、双氧水用量n(H2O2)/n(S)=4、反应温度60℃、反应时间60min和离子液体[BMIM]PF6体积为1mL时,催化氧化脱硫体系[(CH3)4N]4PMo11VO40/[BMIM]PF6/H2O2对含DBT的模拟汽油的脱硫率可达97.8%,该体系对不同硫化物脱硫率大小顺序为DBT4,6-DMDBTBT。在最佳工艺条件下,考察了该体系对FCC汽油的脱硫效果,脱硫后FCC汽油的硫含量为8.6μg/g,符合国Ⅴ汽油标准。该体系可循环使用,循环使用6次后,脱硫率没有明显降低。     

锰/钼催化剂对臭氧微电解处理废水效能的研究

针对印染废水色度高、成分复杂、可生化性差等特点,向铁碳填料中加入锰/钼氧化物作催化剂来提高臭氧微电解工艺对该废水的处理效能。对比处理效果找出填料中锰钼催化剂的添加量。用扫描电子显微镜、傅里叶红外光谱仪等对填料和废水进行表征,探究催化剂在处理印染废水过程中的催化作用。实验结果表明,填料中锰的最佳比例为n(Fe)∶n(Mn)=12∶1,钼的最佳比例为n(Fe)∶n(Mo)=40∶1,COD的去除率分别为91.16%、83.99%,其中铁碳锰填料处理的废水可生化性达到0.66。结合对实验材料的理化表征,综合分析,锰、钼催化剂的催化效果明显,且锰催化剂较优于钼。     

热交换器的分类及优缺点分析

热交换器是将不同温度介质之间的热量通过热传导的形式,由高温介质传递给低温介质,使介质达到生产所需温度的工艺设备,也可作为一种节能设备使用.通过对不同热交换器的结构分析,总结不同热交换器的优缺点、适用环境,为生产工艺设计人员及设备制造单位在选择可降低能耗、提高效率的设备上提供参考.     

聚苯胺及其复合物的制备和结构及形貌分析

通过化学氧化法分别制备盐酸,盐酸和十二烷基苯磺酸,碳纳米管(MWNTs-COOH)掺杂的聚苯胺,利用红外光谱,紫外光谱,扫描电子显微镜和透射电子显微镜对所制备聚苯胺的结构和形貌进行分析。分析不同掺杂物对聚苯胺的结构和形貌的影响;同时研究了超声波作用对聚苯胺形貌以及聚苯胺包裹MWNTs-COOH情况的影响。     

Modelling and computation of curing and damage of thermosets

The curing of thermosets is a complex process involving the transition from a fluid into a (visco-) elastic solid. This phase transition comes along with an increase in stiffness and a volume shrinkage of the polymer. The latter may lead to severe residual strains and stresses, which in turn can cause damage in the final, usually quasi-brittle material. In this contribution a constitutive model is developed which takes into account the curing of a thermosetting material together with the process-induced damage as resulting from curing shrinkage. The curing of the material is governed by a phenomenological hypoelastic constitutive equation which includes temporal evolutions for stiffness and volume shrinkage. Thermal and viscous effects are neglected in the present study. An isotropic gradient-enhanced damage model is adapted to describe the damage evolution. The curing-damage model is implemented into a finite element code and numerical examples for thermosetting materials demonstrate that the proposed model is capable to predict cure-induced damage in thermosets.     

Thermodynamic similarity and prediction of the properties and characteristics of substances and processes

Principles of the theory of thermodynamic similarity are considered in application to all aggregate states of a substance, including phase transitions, and to the change in dissipative structures in open systems.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 53, No. 5, pp. 709–716, November, 1987.     

Mechanisms of Corosion and Oxidation of Metals and Alloys

Selected topics in field of the study of the mechanisms of corrosion and of oxidation of metals or alloys are presented. The first part reports a new model for the mechanism of the breakaway oxidation of ferritic stainless steels in water vapour. The second part is devoted to the physico‐chemical aspects of oxidation and presents experimental methods useful in the kinetic modelling applied to two alloys, the zircalloy‐4 and an AlMg5 % in the liquid state. In the third part the physical and numerical modelling of the stress corrosion cracking behaviour in face‐centered cubic (fcc) alloys is detailed, which enables the study of the influence of macroscopic parameters (such as the temperature or hydrogen activity) on the fracture process.     

碳化硼陶瓷增韧补强和致密化研究现状及其展望

碳化硼陶瓷具有极高的硬度,然而其低韧性、低抗弯强度、难以致密化限制了它的广泛应用.已有一些研究集中于碳化硼陶瓷增韧补强和致密化,对这一方面国内外研究进展进行了归纳与评述,阐明各种增韧补强和致密化方法的优缺点,提出碳化硼陶瓷增韧补强和致密化研究值得发展的一些方向.     

Measurement and analysis of elastic and anelastic properties of alumina and silicon carbide

Measurements of dynamic Young's modulus, E, and damping as a function of temperature, T, were made for alumina and silicon carbide. The Young's modulus data were compared with some from the literature, and analysed in terms of a theoretical framework relating the Debye temperature, θD, with the elastic constants. For both materials this analysis yielded a ratio T₀/θ_D which was near 0.4, where T₀ is an empirical fitting constant for the plot of (E(0)−E)/T versus 1/T (E(0) is the value of E at 0 K). The analysis of the damping data in terms of an Arrhenius type dependence led to effective activation energies near kT, where k is Boltzmann's constant. This revised version was published online in November 2006 with corrections to the Cover Date.     

Preparation and characterization of phosphate and arsenate apatites of strontium and their solid solutions

Samples of phosphate and arsenate apatites of strontium and six of their solid solutions, spread over the entire compositional range, were prepared by a wet method. They were characterized by chemical, X-ray, electron microscopic and infrared analyses. The validity of Vegard's law established the homogeneity of the solid solutions.     

检定和校准证书的异同与应用

本文介绍了检定和校准以及证书的两点相同、五点不同之处,说明了对检定证书和校准证书的正确应用。