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991.
在C++程序设计函数调用过程中,函数参数的传递是至关重要的内容,参数传递的方式不同,其传递的内容也不同类型,在程序设计过程中,选择恰当的参数传递方式,不仅可以使程序更加简洁,同时可以提供程序的运行效率,该文较为全面的论述了C++中函数参数传递的几种常见方式以及各种方式的优点及区别。  相似文献   
992.
Bioresource natural sisal fiber (SF) was used to prepare single fiber‐reinforced isotactic polypropylene (iPP) composites. Three kinds of interfacial crystalline morphologies, spherulites, medium nuclei density transcrystallinity (MD‐TC) and high nuclei density transcrystallinity (HD‐TC), were obtained in the single fiber‐reinforced composites by implementing quiescent or dynamic shear‐enhanced crystallization and by modulating the compatibility interaction between SF and iPP. The development of interfacial shear strength (IFSS) during the interfacial crystallization process was demonstrated for the first time using a combination of single‐fiber fragmentation testing and optical microscope observation. A close correlation between IFSS and morphological characteristics of interfacial crystallization was well elucidated. The increases in IFSS were very different for spherulitic, MD‐TC and HD‐TC morphologies. The highest IFSS obtained was 28 MPa, after the formation of HD‐TC, which was about 62% of the tensile strength of neat iPP (45 MPa). These results offer powerful and direct evidence that interfacial crystallization could play an important role in the enhancement of interfacial adhesion of real SF/iPP composites. © 2013 Society of Chemical Industry  相似文献   
993.
唐钢公司线材产品尺寸精度达到C级品的比例约为74%。为满足用户对C级品盘卷的需求,唐钢高线进行了C级Φ6.5 mm 70硬线试轧实践。根据现有的轧制工艺及设备,在分析C级品的影响因素的基础上,制定了C级硬线试轧方案,对导卫使用、轧辊与导卫装配、关键控制参数等提出了明确要求。试验产品的尺寸精度均达到C级要求,获得用户的好评。  相似文献   
994.
以莴苣为研究对象,通过不同种植状态对比,研究了覆膜栽培方式对莴苣茎和叶片中Cu、Fe、Cd总量和形态的影响及评价。覆膜栽培方式促进了土壤有机质的矿化改变了重金属向莴苣迁移的行为。覆膜方式对莴苣茎和叶中Cu的总量影响很小,但显著增加了莴苣茎中的Cd含量,降低了叶片中Fe的含量,平均增值为0.2 mg/kg和-150 mg/kg。形态分析结果表明覆膜栽培使得莴苣茎中的Fe II向Fe III转化,降低了其在茎中的生物活性,由此导致叶片部位总Fe以及Fe III和Fe IV的减少。覆膜组茎中Cd的活性并没有改变,其总Cd的增加归功于活性最低的Cd IV含量的增加;而叶片中显著增加的CdI形态由于占总量的比例很少,因此覆膜组叶片中总Cd并没有显著增加。两种栽培方式下的莴苣叶中Cd总量均超标,存在食品安全问题,但以每日最大允许摄入量作为参考,3种元素的人均日暴露量均低于ADI值2.4 mg/d、42 mg/d、0.06 mg/d。覆膜栽培方式对人体莴苣叶摄入量贡献率的影响较大,使Fe的贡献率降低了13.1%,而Cd的贡献率增加了6.53%,即增加了摄入镉的潜在风险。  相似文献   
995.
Metal complexes containing a new multi-sulfur atom containing 1,2-dithiolene ligand, [4′,5′:5,6] [1,4] dithiino[2,3-b] quinoxaline-1′,3′-dithiolate, have been synthesized and characterized by electrochemical measurements, IR, UV-NIR and ESR spectroscopies. X-ray structure analysis reveals that the anions of the Ni-complex derived from the new ligand form a zig-zag chain along the b axis, and the anions of Au complex of the ligand stack along the a axis while the cations occupy the holes. The Ni-complex exhibits remarkable absorption at 1082 nm (? = 15?000 dm3 mol−1 cm−1) and good solubility that render this complex as a promising near-IR dye for Q-switching neodymium lasers. The third-order non-linear optical properties of the complexes are measured by the Z-scan technique with a 6.5 ns pulsed laser at 532 nm. The Au complexes exhibit non-linear optical absorptive abilities, while the non-linear absorption of the nickel complex is negligible. All of the complexes show effective self-defocusing performance. The third-order non-linear optical susceptibilities for the Au complexes have been determined to be of the order of 10−13 esu.  相似文献   
996.
Colorimetric artificial nose was used to characterize and identify Chinese liquors from six different geographic origins. Using chemical dyes as the sensing elements, the developed colorimetric artificial nose showed a unique pattern of color changes upon its exposure to Chinese liquors. Data analysis was performed by chemometric techniques: Hierarchical cluster analysis (HCA), principal component analysis (PCA) and linear discriminant analysis (LDA). Each category of Chinese liquor could cluster together in PCA score plot. No errors in classification by HCA were observed in 45 trials. LDA model showed a 100% of prediction ability for Chinese liquor. The results demonstrated that colorimetric artificial nose was able to classify Chinese liquors from different geographic origins.  相似文献   
997.
结合自主研发的预湿浆纱机及多年来的实际应用经验,概述了预湿上浆的工艺机理,总结、分析了预湿上浆技术的应用状况,表明预湿上浆是有待推广应用的先进技术。  相似文献   
998.
Feng  Yu  Mao  Ping-li  Liu  Zheng  Wang  Zhi  Qin  Jia-ming  Wang  Feng 《中国铸造》2016,13(3):159-165
The hot tearing susceptibility of MgZn_(4.5)Y_xZr_(0.5)(x = 0.5, 1, 2, 4, 6) alloys was evaluated using ClyneDavies' theoretical model and a constrained rod casting(CRC) apparatus equipped with a load cell and data acquisition system. The results obtained from these two approaches were in good agreement, illustrating that the hot tearing susceptibility of the investigated alloys is in the order of MgZn_(4.5)Y_xZr_(0.5) MgZn_(4.5)Y_xZr_(0.5) MgZn_(4.5)Y_xZr_(0.5) MgZn_(4.5)Y_xZr_(0.5) MgZn_(4.5)Y_xZr_(0.5). The microstructure and morphology of hot tearing regions were observed by means of X-ray diffraction and scanning electron microscopy. The function curves on variation of contraction force and temperature versus time were recorded by a computer during solidification of the MgZn_(4.5)Y_xZr_(0.5) alloys in a "T" type mold after A/D(Analog to digital) conversion. Results show that both the amount and morphology of the second phases have a great relationship with the hot tearing susceptibility. But the former plays a more important role on that of MgZn_(4.5)Y_xZr_(0.5) alloys. The role of low-melting point eutectic phases on the hot tearing susceptibility of MgZn_(4.5)Y_xZr_(0.5) alloys changes gradually with different Y contents. When Y ≤ 1wt.%, it is mainly a damaging effect on intergranular bonding force; when Y 1wt.%, it is mainly an intergranular feeding effect on formed separated dendrites.  相似文献   
999.
蒋彬  王锐  何嵋  许琴 《山东化工》2012,41(10):98-100
针对来源于边远贫困地区的学生实际,在实验教学中,从实验前的预习、实验台的合理安排、观察记录实验现象、规范操作与仪表等六个方面,分析了无机化学实验中学生的常见问题,并从上述六个方面人手,尝试培养学生的良好实验习惯,收到了积极的效果。  相似文献   
1000.
A mixed phase LaVO4 with high dispersion was in situ induced and implanted in graphene oxide-graphite carbon nitride composite. The obtained nanocomposite (GO–C3N4–LaVO4) showed high and stable photocatalytic activity for hydrogen evolution, which significantly benefited from the improved charge separation and light absorption in the special composite photocatalyst as evidenced by UV–vis spectra, fluorescence spectrum, photocurrent response and electrochemical impedance. The fabrication strategy of mixed phase LaVO4 in the GO-C3N4 provides a new idea for constructing cheap and active organic-inorganic semiconductor photocatalysts for hydrogen generation.  相似文献   
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