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1.
16Mn钢在H2S溶液中的脆断敏感性   总被引:7,自引:0,他引:7  
采用慢性变速率拉伸实验(SSRT)、扫描电镜及电化学渗氢技术研究了H2S浓度、电位对16Mn钢在H2S溶液中脆断敏感性的影响,结果表明:16Mn钢在H2S溶液中的断裂是一种氢脆控制的断裂,随H2S浓度(N)增大,应力腐蚀断裂的机理从韧性转变的脆性;16Mn钢片在H2S溶液中的稳态渗氢电流值IH和H2S浓度(N)满足IH=8.525×N^0.7249;IH受温度的影响主要表现在氢在16Nn钢中的扩散  相似文献   

2.
以原子氢渗透速率测量传感器作为信号元件,80C31单片机作为中央处理单元,利用钢铁(A3钢和16Mn钢)在酸洗溶洗液中发生氢致腐蚀裂开危险性的临界条件为基本参数而编写了系统程序和专门设计了外国电路,研究并建立了钢铁在酸洗过程中发生氢致腐蚀开裂危险性的数据采集,存储处理,逻辑判断以及结果自动制表打印输出功能的微机系统。  相似文献   

3.
16Mn钢轧后控制冷却的贝氏体组织与性能   总被引:2,自引:0,他引:2  
研究了16Mn钢轧后会冷却工艺对贝氏体组织与性能影响,结果表明,采取适当的控冷工艺所得到细化铁素体和粒状贝氏体组织,可使16Mn钢获得良好手强韧性配合,文中还对16Mn钢轧后控冷所产生的贝氏体组织进行了分析。  相似文献   

4.
16Mnq钢用于焊接桥梁的防断适用性研究(待续)   总被引:1,自引:0,他引:1  
在分析国外桥规中防断选材规则的基础上,提出了将16Mnq钢用于焊接桥梁时的韧性要求,纳入焊接桥梁防断设计的完整体系加以考察,采用了断裂力学K概念的基本思路。根据深缺口宽板拉伸试验,夏比V型缺口冲击试验得到的16Mnq钢大量试验结果,进行了规律性的统计分析,给出了16Mnq钢及其焊接接头的断裂抗力表达式;根据设计规范和钢桥典型结构件的内应力分析,规定了焊接桥梁各类构件的驱动力分类。提出了16Mnq钢按韧性分级使用的建议,最终给出了对应于构件类别、最低设计温度所允许使用的16Mnq钢各韧性级别的极限厚度表。文末,以16Mnq钢韧性分级使用为共同基础,将本研究工作的最终结果分别与执行英国桥规和其它实用性防断判据所得结果进行对比。本文的结论意见既包括了纳规建议,又涉及了关于后续工作建议。  相似文献   

5.
16Mnq钢用于焊接桥梁的防断适用性研究(续)洛阳船舶材料研究所刘家驹,蒋和岁,严明君,毕传堂416Mnq钢及其焊接接头的断裂抗力本文所述试验用材料为16Mnq钢及其相应的焊接接头板。其中,32mm,24mm和16mm厚钢板各3个批号,12mm厚钢板...  相似文献   

6.
研究了氢蚀温度对20G和15CrMo钢常规力学性能与疲劳性能和机制的影响以及应力比对氢蚀后20G钢疲劳性能的影响结果表明,氢蚀后20G钢的疲劳行为受氢蚀对材料损伤程度和氢蚀导致粗糙的裂纹途径造成闭合效应增加两因素联合作用;氢蚀后15CrMo钢脱碳严重,其疲劳行为仅受脱碳对材料损伤作用的影响;应力比对20G疲劳性能也有很大影响  相似文献   

7.
用电化学渗透法分别研究了65Mn钢五种不同组织对氢扩散系数和陷阱能的影响,结果表明,珠光体,球化珠光体,回火索氏体,下贝氏体,回火马氏体的陷阱能分别为16.71、30.32、31.35、31.01、35.61(KJ/mol)。  相似文献   

8.
3种船用钢在南海海洋环境中8年的腐蚀行为   总被引:2,自引:0,他引:2  
研究了3C(W )、16Mn、921 三种钢在南海榆林海域全浸、潮差、飞溅环境中暴露8 年的腐蚀行为。其中,921 钢在飞溅区具有优良的耐蚀性,而在全浸和潮差区耐蚀性不如3C(W)钢和16Mn 钢的。发现921 钢在全浸区暴露2 年后发生腐蚀率随时间增加而增大的“逆转”现象。  相似文献   

9.
16Mnq钢用于焊接桥梁的防断适用性研究(续完)洛阳船舶材料研究所刘家驹,蒋和岁,严明君,毕传堂616Mnq钢用于焊接桥梁的分级使用在本文第4节,已提出了以大量试验为基础,考虑了加载速率和裂纹尖锐度的影响后的16Mnq钢板及焊缝金属的断裂抗力表达式(...  相似文献   

10.
研究了氢蚀温度对20G和15CrMo钢常规力学性能疲劳性能和机制的影响以在力比对腐蚀后20G钢疲劳性能的影响,结果表明,氢蚀后20G钢的疲劳氢蚀对材料损伤程度和氢蚀导致和粗糙内裂纹途径造成产合效应增加两因素联合作用,氢蚀后15CrMo钢脱碳严重,其疲劳行为仪受脱碳对材料的损伤作用的影响,应力比对20G疲劳性能也有很大影响。  相似文献   

11.
采用程序升温脱附实验方法测量氧的同位素C16O2,C18O2和18O2分别在Ni16O表面吸附后的脱附谱,其结果表明C16O2在Ni16O表面吸附后出现C16O2和C16O两个波峰,且C16O2和C16O的脱附量随C16O2气体暴露量增加而增加,其峰值温度随C16O2气体暴露量增加而减少,当C16O2气体覆盖度超过一定值后,C16O2和C16O脱附量趋于常数,其活化能分别是0.48 eV和0.42 eV。C18O2在Ni16O表面吸附后出现C16O2,C18O16O,C18O2三个波峰,这说明吸附气体C18O2与Ni16O表面发生氧同位素交换,随温度升高而脱附出C16O2;18O2在NiO表面吸附后主要以18O2脱附,说明了富18O2有相对抑制与Ni16O表面氧的同位素交换的作用。  相似文献   

12.
离子液体/磷酸锆抗菌材料的制备及耐热性研究   总被引:1,自引:0,他引:1  
李丹  陈运法 《无机材料学报》2011,26(11):1193-1198
以α-磷酸锆(分子式: Zr(HPO4)2·H2O, 以下简称α-ZrP)为载体, 三种季铵型离子液体: 溴化十六烷基三甲基咪唑(C16MIMBr)、氯化十六烷基二甲基苄基铵(C16HDBACCl)和氯化十六烷基三甲基铵(C16CTACCl)被引入α-ZrP层间, 制备得到三种离子液体/α-磷酸锆(IL-ZrP)复合抗菌材料. 通过X射线衍射法(XRD)、红外光谱分析(FTIR)、热重-红外联用分析(TG-FTIR)对材料的结构、组成和热稳定性进行表征. XRD结果表明: 相对于α-ZrP, 三种复合抗菌材料的层间距明显增大, 这证明离子液体已经成功地嵌入到α-ZrP的层间. TG-FTIR实验显示三种离子液体在复合抗菌材料中分别占53.11wt%、50.65wt%和51.25wt%. 三种纯离子液体的热分解起始温度分别为174℃、198℃和219℃, 而离子液体/α-ZrP(IL-ZrP)复合抗菌材料中所含的离子液体的热分解起始温度为219℃、225℃和263℃, 这表明α-ZrP能有效提高离子液体的耐热性. 抗菌性能检测结果表明: 在三种复合材料中, C16MIMBr-ZrP具有较好的抗菌效果(在24 h内, 其对大肠杆菌、金色葡萄球菌的最小抑菌浓度均小于19 mg/L).  相似文献   

13.
采用复合铸造法制备了钢/锌复合材料研究其阻尼性能.在拉伸条件下分析其阻尼机制以及拉伸过程中材料的变形行为;在循环条件下测试其阻尼性能与应变幅值的关系;通过衰减实验测试其阻尼性能与材料的几何性质的关系;同时,在三种实验条件下对比钢/锌复合材料和单相钢和锌的阻尼性能.实验结果表明,钢/锌复合材料较钢改善了阻尼性能,较锌则提高了刚度和强度;钢及钢/锌复合材料的阻尼性能具有应变依赖性;复合材料的几何特性对其阻尼性能有一定的影响.  相似文献   

14.
Increased percentage of monocytes with low CD14 expression and that co-express CD16 (CD14+/CD16+) have been reported in hemodialysis (HD) patients. We sought to determine whether CD14+/CD16+ monocytes in HD therapy are sensibilized cells to a proinflammatory activity. Cells from 32 HD patients, and from 9 Systemic Lupus Erythematosus (SLE), 9 individuals with human immunodeficiency virus (HIV)-1- and 15 healthy controls were studied. Cells were analyzed by means of flow cytometry for CD14/CD16 expression and immune function (cytokine, chemokines, and sialoadhesin expression), and phagocytosis. Increased percentage of CD14+/CD16+ monocytes was observed in HD patients. Compared with CD14++ monocytes, the CD14+/CD16+ monocytes exhibited increased expression of proinflammatory cytokines and markers of differentiated cells. In addition, these monocytes showed an increased phagocytic activity. Similarly, CD14+/CD16+ monocytes from SLE and HIV patients showed increased inflammatory activity as compared with CD14++ cells. These results support that CD14+/CD16+ monocytes from HD patients evidence characteristics of primed prestimulated proinflammatory cells, similar to data observed in SLE and HIV.  相似文献   

15.
介绍了一套简单、低成本的制作二极管型碳基膜场发射显示器模块的制作方法.该显示单元模块为16 * 16矩阵型点阵,可根据实际需要拼接成各种尺寸.器件的阴极和阳极均采用丝网印刷技术,包括:阴极导电图形、CNT图形、阳极荧光图形的印刷.各膜层图形经过精心设计以实现矩阵选址.使用低玻粉将阴极和阳极烧结之后,采用超高真空排气台进行排气,然后装配上驱动电路,即实现了单元碳基膜场发射显示器模块的制作.另外,为了改善CRT荧光粉的黏附性差和电阻率低的问题,我们往CRT荧光粉浆料中分别加入了碳纳米管和硝酸镁,得到了更好的发光性能.  相似文献   

16.
FSM-16,MCM-41和SBA-15等具有高规则二维六角晶格的多孔硅可用不同硅源和表面活性剂合成,其孔径可达10,15或30nm,可用具有不同熔基链长的表面活性剂和膨胀剂控制。其结晶规则性随孔径的增大而降低。用层状硅土Kanemite制备的FSM-16和来自水玻璃的MCM-41,其表面阴离子度比用四甲氧基硅烷(TMOS)制备的SBA-15高得多。如将在等电点以下呈阴离子性的生物酶插入硅孔,则由于离子间的相互作用和氢键结合力,可得到结合得十分稳定的生物/无机陶瓷结合体。以此结合体为有机酸化反应的催化剂,反应的活性很高。  相似文献   

17.
Shen JJ  You CF 《Analytical chemistry》2003,75(9):1972-1977
Boron isotopes are potentially very important to cosmochemistry, geochemistry, and paleoceanography. However, the application has been hampered by the large sample required for positive thermal ionization mass spectrometry (PTIMS), and high mass fractionation for negative-TIMS (NTIMS). Running as BO(2)(-), NTIMS is very sensitive and requires only nanogram sized samples, but it has rather poor precision (approximately 0.7-2.0 per thousand) as a result of the larger mass fractionation associated with the relatively light ion. In contrast, running as the much heavier molecule of Cs(2)BO(2)(+), PTIMS usually achieves better precision around 0.1-0.4 per thousand. Moreover, there is a consistent 10 per thousand offset in the (11)B/(10)B ratio for NIST SRM 951 standard boric acid between the NTIMS and the certified value, but the cause of this offset is unclear. In this paper, we have adapted a technique we developed earlier to measure the (138)La/(139)La using LaO(+) (1) to improve the NTIMS technique for BO(2). We were able to correct for instrumental fractionation by measuring BO(2)(-) species not only at masses of 42 and 43, but also at 45, which enabled us to normalize (45)BO(2)/(43)BO(2) to an empirical (18)O/(16)O value. We found that both I(45)/I(42) = ((11)B(16)O(18)O/(10)B(16)O(16)O) and (I(43)/I(42))(C) = ((11)B(16)O(16)O/(10)B(16)O(16)O) vary linearly with (I(45)/I(43))(C) x 0.5 = ((11)B(16)O(18)O/(11)B(16)O(16)O) x 0.5 = (18)O/(16)O. In addition, different activators and different chemical forms of B yield different slopes for the fractionation lines. After normalizing (11)B(16)O(18)O/(11)B(16)O(16)O x 0.5 to a fixed (18)O/(16)O value, we obtained a mean (11)B/(10)B value of NIST SRM 951 that matches the NIST certified value at 4.0430 +/- 0.0015 (+/-0.36 per thousand, n = 11). As a result, our technique can achieve precision and accuracy comparable to that of PTIMS with only 1 per thousand of the sample required. This new NTIMS technique for B isotopes is critical to the studies of early solids in the solar system and individual foraminifera in sediments that require both high sensitivity and precision.  相似文献   

18.
From the product of fluorination of [60]fullerene with K2PtF6 at 470 °C, we have isolated a small quantity (ca. 0.5 mg) of C60F16O, an oxahomofluorofullerene (ether) of exceptionally long HPLC retention time (50% greater than any other known fluorofullerene). The 19F NMR spectrum consists of 16 main lines and 8 minor ones, due to C60F16O (a single isomer of C1 symmetry) and C60F16, respectively. The presence of the latter (absent on initial isolation) indicates this ether to be relatively unstable, confirmed by the failure to obtain an EI mass spectrum. The empirical formula was therefore determined by MALDI-TOF mass spectrometry in the negative-ion mode, the laser fluence being carefully adjusted at the threshold of ion formation, whence the only observable signal corresponded to the molecular ion of C60F16O. At slightly higher laser fluence, the base peak of C60F16O·- is accompanied by C60F16·- and C60F15O·-. Two closely similar structures (of similar calculated stabilities) are fully consistent with the NMR data. Calculated dipole moments and the exceptionally long retention HPLC retention times suggest that both C60F16 and C60F16O may be dimers.  相似文献   

19.
Several asynchronous-logic macrocells for a cell library for low-voltage (1.1 V) power-critical applications are described. The intended application is for the realisation of the datapath of an embedded asynchronous digital signal processor in low-voltage power-critical digital hearing instruments where the speed is relatively low, <5 MHz. The macrocells are two 2-bit and three 16-bit adders, a 16times16-bit truncated parallel multiplier and a 16-bit accumulator. Compared to reported 2-bit adders, one of the 2-bit adders features the lowest energy-delay product (EDP), whereas the other features the lowest energy (power/MHz). Among the three proposed 16-bit adders, two of them feature the lowest EDP compared to the reported designs, and their completion detection circuit is very simple (an OR gate). The truncated parallel 16times16-bit multiplier features the lowest energy multiplier in the literature and this is achieved by truncation and by means of a proposed integrated latch-cum-adder (latch adder) that virtually eliminates the spurious switching in the adder block. The accumulator features the lowest energy accumulator, also by means of the latch adder embodied therein. All macrocells are verified by computer simulations and on the basis of measurements on prototype ICs  相似文献   

20.
The FSM-16, MCM-41 and SBA-15 type hexagonal mesoporous silica materials having a highly arrange in order of the 2-dimensional structure were synthesized by using different silicon sources and surfactants. In the 2-dimensional silicate framework, pore size can be uniformly controlled by the combined use of the surfactants having different alkyl chains length and swelling agents (triisopropyl benzene). Pore-diameter of FSM-16 and MCM-41 can be expanded to 100 A, SBA-15 is 150 A. Crystal regularity decreased with increasing the pore-diameter in the FSM-16 derived from Kanemite (silicon source) and MCM-41 from water glass, its anionic char-acteristics on the pore wall may be higher than SBA-15 derived from oligomeric tetramethoxysilane (TMOS) is also reported. We have successfully used FSM-16 and MCM-41 as immobilizing agents of enzyme having cationic residues under isoelectric point. The level of adsorption of enzymes in the FSM-16 and MCM-41 was relatively high, but was low in the SBA-15 support. The mechanism of enzyme adsorption in mesopore was suggested to be the ionic interactions. In aqueous solutions, horseradish peroxidase (HRP) immobilized in FSM-16 containing 89A mesopore showed the highest loaded amounts(183mg/mg FSM),then a FSM-16 of pore-diameter 30 A only loaded a litter amounts (28mg/mg FSM) on the outside surface. The catalytic activity in organic solvent is high when HRP was immobilized in FSM-16 and MCM-41, but is low in case of SBA- 15.  相似文献   

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