吸光光度法测定裂解气压缩机注水中溶解氧

提出了测定裂解气压缩机注水中溶解氧含量的吸光光度法。测定波长为600 nm。溶解氧浓度在10~100μg·L-1范围内与吸光度呈线性关系,检出浓度为2μg·L-1。方法简便、灵敏、准确,可用于直接测定水样中的溶解氧。     

Ti-ZSM-5分子筛的裂解催化行为

含钛分子筛的水热合成工作已有报道,有关催化性能的研究尚未见报,本文报道了十五烷裂解反应中Ti-ZSM-5分子筛的催化行为,所用Ti-ZSM-5分子筛的合成与表征见文献[2]。     

交联镓皂石表面酸性及催化性能的研究

用水热法合成出两种不同镓含量的镓皂石，并用羟基铝低聚物对其进行了交联。对其表面酸性的考察发现，样品的酸量随嫁含量的增加而增大；样品均含有Ｂ酸和Ｌ酸中心，交联样品的Ｂ酸中心比交联前少。对样品催化性能的研究发现，催化活性与镓含量及酸量呈顺变关系。     

有关绥李三号裂果因子的研究

以绥李三号、绫棱红、吉林六号为试材,对影响裂果的生理指标进行了测试,结果表明,果实硬度不均匀性促进果实开裂,水分影响裂果,而可溶性固性物含量与裂果无明显相关。在防止措施上,喷施硼砂溶液可减轻裂果比率。     

Crack growth rate and cracking velocity in fatigue for a class of ceramics

Fatigue crack growth rate data and cracking velocity data are studied for a class of ceramics including SiC, TiB₂, Si₃N₄, ZrO₂ and Al₂O₃. Both sine and square wave cyclic loading are combined such that the data could be converted to cracking velocity for a given frequency of cyclic load. An effective stress intensity factor range is defined and used in an relation for computing the crack growth rate and cracking velocity. As for the metal alloys, the data for ceramics also fall into three regimes identified with near-threshold, stable growth and rapid crack extension, except that the slope of the da/dN (the crack growth rate) curves for ceramics are steeper in comparison with that for metals. Reported are the empirical constants in the relations for the crack growth rate and the cracking velocity for a variety of ceramics.     

铝和磷对催化裂化催化剂抗镍性能的影响

选择Ａｌ和Ｐ元素作为催化裂化催化剂的钝镍组分，并用裂化反应产物中氢气含量、微活指数（ＭＡＴ）、积炭量等指标对元素Ａｌ和Ｐ的钝镍效果进行了考察。结果表明，Ａｌ和Ｐ均能降低裂化反应产物中的氢气含量，Ａｌ能提高催化剂的裂解活性，而Ｐ能减少催化剂上的积炭。因此，Ａｌ和Ｐ对抑制Ｎｉ污染都有明显效果。     

Investigation of temperature and stress fields in laser cladded coatings

Temporal and spatial distributions of temperature and strain-stress have been modelled and investigated experimentally for the laser cladding process. The model corresponded to experimental conditions where the multilayer protective coatings were prepared by direct laser cladding of stellite SF6 powder on X10Cr13 chromium steel by means of a 1.2 kW CO₂ laser. For calculations the effect of base preheating, temperature dependent material properties, and also influence of time-break between cladding of the consecutive layers were taken into account. The calculated temperature fields indicated good bonding of the substrate and coating, which was in agreement with the micro-analytical test results. A decrease of the number of microcracks in the coating with an increase of substrate preheating temperature was concluded from stress calculations and confirmed in the experiment. Moreover, an increase of the cracking susceptibility with an increase of the time delay between cladding of the consecutive layers was evidenced by modelling. The best technological results were obtained for the case of single-layer coatings prepared on a preheated substrate and for higher coating thickness required the processing of consecutive layers with a possibly short time delay is advisable due to effective usage of laser beam energy for preheating and lower temperature gradients.     

Monitoring of drying process and cracking/disbonding of paints using lensless Fourier transform digital holography

We have proposed and demonstrated a new application of lensless Fourier transform digital holographic interferometry to study/monitor the drying process and detection of cracking/disbonding of the painted surface by observing the dynamics of interference phase maps. The technique can monitor the rate of drying of paint and visualize the state of dryness and crack/disbond. The technique is simple and easy to implement.     

POLYMERIC ACID FOR THIN FILM APPLICATIONS

ABSTRACT

Propyl and butyl half esters of the alternating copolymer isobutylene/maleic anhydride (IB/MAn) are polymers of high acid content (4.67 and 4.38 milliequivalent acid/g polymer). These polymers exhibit good physical performance in thin films, such as absence of cracking and minimal curl. The anhydride ring of the copolymer IB/MAn is opened in refluxing alcohol at atmospheric or elevated pressure; conversion is monitored by an IR probe (1783 vs. 1733 cm?1). The polymers are stable up to about 50 °C. Weight loss corresponding to the reversion to the anhydride structure is observed at higher temperature, with concurrent increase of anhydride resonances in the IR. Thermal stability of the half esters is similar to that of alkyl half esters of the alternating copolymers ethylene/maleic anhydride (EMA) and methyl vinyl ether/maleic anhydride (Gantrez® AN 119). The 1-propanol solution of the propyl half ester of IB/MAn copolymer is a shear thinning fluid, a significant advantage when coating at high speeds.     

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通过电子束辐照实验和有限元模拟研究了ITER类型面对等离子体的高纯钨材料在瞬态热冲击下的行为。在新建成的电子束实验平台EMS-60上进行了ITER等离子体发生大破裂不稳定下的模拟实验,实验中样品的基体温度为室温,脉冲宽度为1-5ms,能量负载范围是1~5MJ-m-2。实验后通过扫描电镜观察了样品的再结晶、裂纹及熔化情况,讨论了裂纹形成机理。通过有限元模拟,得出在5ms的脉冲负载下钨的裂纹阈值为1.5MJ-m-2,与实验结果符合很好。