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31.
32.
W. R. Miller E. W. Bell J. C. Cowan H. M. Teeter 《Journal of the American Oil Chemists' Society》1961,38(5):235-237
The reaction of dimethyl maleate and some related dienophiles with vegetable oils under pressure has been studied successfully.
When safflower oil reacts with 100% excess maleate, sulfur dioxide catalyst, and hydroquinone inhibitor at 290° for 1hr.,
80 to 90% yields of adduct fraction, based on linoleate, are obtained. Under the same conditions almost equally good yields
result with either linseed or soybean oils. With safflower oil, dimethyl fumarate gave slightly lower yields. Di-n-butyl maleate gave even poorer yields, and much residue was formed.
Paper II in a series entitled, “Reactions of Dienophiles with Vegetable Oils”. Presented at annual meeting, American Oil Chemists'
Society, St. Louis, Mo., May 1–3, 1961.
This is a laboratory of the Northern Utilization Research and Development Division, Agricultural Research Service, U.S. Department
of Agriculture. 相似文献
33.
Protein, total phospholipid, phosphatidyl cholines and phosphatidyl choline fractions from liver mitochondria and microsomes
of female rats were analyzed after treatment with CCl4 (0.3 ml of CCl4 suspended in corn oil) or ethionine (50 mg in 0.9% saline) or after feeding a choline deficient, low protein diet for seven
days. Phosphatidyl cholines were separated into four fractions differing in the degree of fatty acid unsaturation. Over 50%
of total phosphatidyl choline phosphorus was present in fraction 3 of liver mitochondria and microsomes. The major fatty acid
in fraction 1 was docosahexaenoic acid. Fraction 4 contains oleic and linoleic acids. Arachidonic acid occurs in fraction
2 and 3. Ethionine decreased the amount of microsomal protein and phosphatidyl choline fraction 1 of mitochondria. Microsomal
protein was decreased by CCl4. The choline deficient, low protein diet caused a decrease in mitochondrial and microsomal phospholipids. The amount of the
mitochondrial phosphatidyl choline decreased. Corn oil increased the level of phosphatidyl choline fraction 3. Choline deficiency
decreased the amount of phosphatidyl choline fraction 3, increased fraction 4 of mitochondria and microsomes and increased
fraction 1 of microsomes. 相似文献
34.
Saturated fluorocarbon elastomers are very resistant to chemical reactions, including those of a crosslinking nature. In order to study proper methods of preparing these materials, Viton GLT was mixed with various levels of trimethylol propane trimethacrylate, TMPTM, and triallyl isocyanurate, Diak #7. After molding, the materials were subjected to electron beam irradiation. The glass transition, rubbery modulus, viscoelastic behavior, and equilibrium swelling were used to characterize the materials as a function of crosslinker and irradiation level. In general, the modulus and gel fraction increased with both crosslinker content and irradiation level. Mixtures of both crosslinking monomers produced an unexpected synergism, yielding higher tensile strength, and earlier onset of gelation. 相似文献
35.
DALLY B B 《中国科学:信息科学(英文版)》2011,(2)
Moderate or intense low oxygen dilution(MILD)combustion plays a significant role in the mitigation of combustion-generated pollutants and greenhouse gases whilst meeting thermal efficiency needs.However,due to the lack of the fundamental knowledge on this combustion,there is a misconception that MILD combustion should be established by high preheating of the air,which has limited its application.Our research and development on this combustion has been performed for several years. We have found that the requ... 相似文献
36.
窄带滤光片是应用于光谱学、激光、天文物理学、通信等各个领域的光学组件,精确控制每一层膜厚是制备滤光片的困难所在.采用光学极值法直接监控工件,可以同时制备多件滤光片.设计了监控光路和信号获得电路,通过探测到的测试信号,监控薄膜膜厚,实现了直接监控. 相似文献
37.
An experimental study of the gas-dynamic aspects of the high-velocity oxyfuel (HVOF) thermal spray process has been performed
using commercially available HVOF equipment (Hobart-Tafa JP-5000, Ho-bart-Tafa Technologies, Inc., Concord, NH). Optical diagnostic
techniques, including microsecond-expo-sure schlieren and shadowgraph imaging, were applied to visualize the hot supersonic
jet produced by this equipment without particle injection. Rapid turbulent mixing of the jet with the surrounding atmos-phere
was observed, which is an issue of concern in coating quality due to the possibility of oxidation of sprayed particles. This
mixing appears to be a function of the ratio of densities of the hot jet and the cold atmosphere as well as a function of
the velocity of the jet, rather than one of combustion-chamber pres-sure or barrel length. The supersonic core of the HVOF
jet dissipates rapidly due to the mixing, so that the jet is no longer supersonic when it impinges on the target surface being
sprayed. Secondary issues also observed in this study include strong jet-noise radiation from the HVOF plume and the entrainment
and induced bulk motion of the surrounding air. 相似文献
38.
Academic librarians have shared their experiences with tablet computers, but few examine how librarians use tablets in their instruction design. While the education literature provides technology integration models, the nature of library instruction requires adapting these models to the library classroom. After reviewing literature related to tablets in library instruction and a number of technology integration frameworks, this article demonstrates an application of the Substitution, Augmentation, Modification, Redefinition framework to analyze observations of an iPad-equipped classroom at a university library. Demonstrating this use of a framework provides an approach to technology integration and continues the discussion about tablets’ potential to promote innovative pedagogy. 相似文献
39.
KD Miller 《Canadian Metallurgical Quarterly》1994,7(4):1-12
Although Hodgkin's disease is considered one of the "curable" cancers, the high cure rates associated with this disease are not accomplished without risk of potentially severe, immediate, and late side effects. Because the predominant histologic subtype of Hodgkin's disease found in the United States generally affects the 15- to 25-year-old age group, the disease, its treatment, and the side effects of treatment will affect many women of childbearing age. The treatment and its effects on the patient and offspring, including posttreatment fertility, are key issues for perinatal nurses. 相似文献
40.
Intravenous infusion of mice with viable allogeneic lymphocytes can produce donor-specific enhancement of skin graft survival, but only if the injected lymphocytes can persist in the host's recirculating lymphocyte pool for at least 3 days. We have investigated the relative roles of class I and class II MHC for C57BL/6 mice infused with lymphoid cells from co-isogenic strains mutated at class I MHC (bm1) or class II MHC (bm12), and for A.TH lymphoid cells infused into C3H (class I different, class II identical) or A.TH (class II different, class I identical). Injected cells differing from the host at class I MHC, but not at class II MHC, can be rapidly removed by host natural immune mechanisms (probably NK cells). Persistence is favored if the injected cells also carry host class I MHC, i.e., tolerance is more readily induced by injecting F1 (A x B) into A rather than B into A, consistent with the "missing self" hypothesis of NK recognition, with class I MHC being the relevant self-marker. Injected cells differing from the host at class II MHC but not at class I MHC always persist for at least 3 days, even when class I-different cells are being actively removed. 相似文献