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121.
Edmund F. Jordan Jr. William E. Palm William S. Port 《Journal of the American Oil Chemists' Society》1961,38(5):231-233
Coplymers of acrylonitrile containing 5 to 28 mole % (11 to 70 weight %) of three alkyl acrylates (butyl, octyl, and octadecyl)
were prepared in t-butanol solution. The copolymers were capable of being molded at about 300–400°F. under a pressure of about
2,000 p.s.i. The magnitude of both the tensile strength and the characteristic low temperature of the copolymers varied inversely
with the weight percentage of the acrylate present without regard to its alkyl type. The copolymers were oriented with an
accompanying three-fold increase in the tensile strength. Good resistance to several selected reagents was shown by all the
copolymers.
This paper was presented, in part, at the fall meeting. American Oil Chemists' Society, New York, October 1960.
Eastern Utilization Research and Development Division, Agricultural Research Service, U.S. Department of Agriculture. 相似文献
122.
Administered a Ward Climate Inventory to 173 staff and 254 patients on 7 male wards of a neuropsychiatric hospital. 3 factors emerged from analyses: Factor I-personnel concern for patients; Factor II-patient concern for patients; and Factor III-ward morale. Elopement rate was significantly correlated with staff scores on Factors I and III and with magnitude of patient-staff differences on Factors I and III. Higher elopement rates were associated with lower personnel concern for patients, lower ward morale, and smaller patient-staff discrepancies in perceived personnel concern and ward morale. Release rates and community stay of unmarried schizophrenics were positively correlated with the patient-staff discrepancy score for Factor I. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
123.
Four combinations of prilled fat and canola oil were fed to 10 lactating Holstein cows in a replicated 5 x 5 Latin square to determine whether mixing plant oil with a rumen inert fat had additive effects on digestive and lactation responses. Five diets of concentrate and corn silage (1:1, DM basis) contained either no added fat (control) or 5% fat comprising 100, 67, 33, or 0% prilled fat and the remainder canola oil. The fat supplement containing 100% prilled fat appeared to be rumen-inert because it caused no changes in ruminal VFA concentration, acetate to propionate ratio, or total tract fiber digestion. Prilled fat increased milk production, FCM, and milk fat percentage but decreased milk protein percentage, including casein content. Increasing canola oil in the fat supplement caused linear declines in ruminal VFA, acetate to propionate ratio, and milk production. Milk production efficiency (weight FCM/weight DMI) exceeded the control diet when fat supplements contained 100 or 67% prilled fat but dropped below control for 33 and 0% prilled fat. This study demonstrates additive effects of combining canola oil with hydrogenated, prilled fat on ruminal fermentation but nonadditive effects on milk production efficiency and milk composition. At low levels of supplementation, plant oils, such as the canola oil used in this study, can inhibit ruminal fermentation but still maintain milk production efficiency. 相似文献
124.
Grit Walther Jenny Steinborn Thomas Stefan Spengler Tobias Luger Christoph Herrmann 《The International Journal of Advanced Manufacturing Technology》2010,47(5-8):461-474
Reducing the quantity of waste for disposal and saving natural resources were main drivers for the introduction of the European Directive on waste electrical and electronic equipment (WEEE-directive). This policy focused on an extension of the producer responsibility (EPR) to the end-of-life-phase of their products. Because of the EPR concept, the national transposition of the WEEE-directive, especially the German transposition in the law ElektroG, caused changes in the organisation and material flows that are sometimes not in line with the aim of the directive, which is to enforce the waste management premise “avoidance prior recycling prior disposal”. Thus, the objective of this contribution is to analyse and compare the situation before and after implementation of the ElektroG in Germany, and deduce improvement potentials. Therefore, a co-operation of a municipality and a nearby disassembly company in Germany is analysed and evaluated, taking into account material flows and costs before/after implementation of the ElektroG, as well as degrees of freedom. Based on this analysis, recommendations are deduced for political decision makers and actors of the WEEE treatment system. 相似文献
125.
Brazil nuts were shelled and separated as kernel and brown skin; whole nuts were also used. Soluble phenolics from each portion as well as the whole nut were extracted using 70% acetone under reflux conditions. Insoluble-bound phenolics were subsequently extracted into diethyl ether–ethyl acetate mixture (1:1, v/v) after alkaline hydrolysis. Both soluble and insoluble-bound phenolic extracts were separately examined for their total phenolics content; antioxidant activities were evaluated by trolox equivalent antioxidant capacity (TEAC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and hydroxyl radical scavenging activities using electron paramagnetic resonance (EPR), reducing power, and oxygen radical scavenging capacity (ORAC). Soluble phenolics in brown skin was 1236.07 as compared to 406.83 in kernel and 519.11 mg/100 g in whole nut. Bound phenolics content of brown skin was also 86- and 19-folds higher than kernel and whole nut, respectively. Similarly extracts from the brown skin exhibited the highest antioxidant activity. Free- and bound phenolics were identified and quantified; these included nine phenolic acids and flavonoids and their derivatives (gallic acid, gallocatechin. protocatechuic acid, catechin, vanillic acid, taxifolin, myricetin, ellagic acid, and quercetin). However, some phenolics were present only in the bound form. Furthermore, the phenolics were dominant in the brown skin. 相似文献
126.
Nyholm JR Asamoah RK van der Wal L Danielsson C Andersson PL 《Environmental science & technology》2010,44(23):9189-9194
In the present study the accumulation potentials in earthworms (Eisenia fetida) of selected brominated flame retardants (BFRs) were investigated. The tested BFRs, including polybrominated diphenyl ethers (PBDEs), hexabromobenzene (HBB), and 1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane (TBECH), were found to be bioavailable to Eisenia fetida, and they accumulated in the earthworms. To our knowledge, this is the first published study to address the bioaccumulation potential of TBECH in terrestrial biota. Aging the soil resulted in decreased accumulation of TBECH, HBB, and PBDEs with six or less bromine atoms. However, no effect of soil aging was seen for BDEs 183 or 209, possibly due to their low mobility in soil. The use of different soils (artificial OECD soil and two natural Swedish soils) also affected the degree of accumulation in the worms. The results indicate that use of the generally accepted standard OECD soil may overestimate accumulation of organic contaminants by earthworms, due to high bioavailability of the contaminants and/or weight loss of the worms in it. Further, the accumulation of selected PBDEs and HBB was compared to the accumulation of their chlorinated analogues. Brominated compounds accumulated to the same or a lesser extent than their chlorinated counterparts. 相似文献
127.
Ciara N. Murphy Susan P. Walker Teresa M. MacDonald Emerson Keenan Natalie J. Hannan Mary E. Wlodek Jenny Myers Jessica F. Briffa Tania Romano Alexandra Roddy Mitchell Carole-Anne Whigham Ping Cannon Tuong-Vi Nguyen Manju Kandel Natasha Pritchard Stephen Tong Tuuhevaha J. Kaituu-Lino 《International journal of molecular sciences》2021,22(14)
Biomarkers for placental dysfunction are currently lacking. We recently identified SPINT1 as a novel biomarker; SPINT2 is a functionally related placental protease inhibitor. This study aimed to characterise SPINT2 expression in placental insufficiency. Circulating SPINT2 was assessed in three prospective cohorts, collected at the following: (1) term delivery (n = 227), (2) 36 weeks (n = 364), and (3) 24–34 weeks’ (n = 294) gestation. SPINT2 was also measured in the plasma and placentas of women with established placental disease at preterm (<34 weeks) delivery. Using first-trimester human trophoblast stem cells, SPINT2 expression was assessed in hypoxia/normoxia (1% vs. 8% O2), and following inflammatory cytokine treatment (TNFα, IL-6). Placental SPINT2 mRNA was measured in a rat model of late-gestational foetal growth restriction. At 36 weeks, circulating SPINT2 was elevated in patients who later developed preeclampsia (p = 0.028; median = 2233 pg/mL vs. controls, median = 1644 pg/mL), or delivered a small-for-gestational-age infant (p = 0.002; median = 2109 pg/mL vs. controls, median = 1614 pg/mL). SPINT2 was elevated in the placentas of patients who required delivery for preterm preeclampsia (p = 0.025). Though inflammatory cytokines had no effect, hypoxia increased SPINT2 in cytotrophoblast stem cells, and its expression was elevated in the placental labyrinth of growth-restricted rats. These findings suggest elevated SPINT2 is associated with placental insufficiency. 相似文献
128.
Tracey M. Clarke Amy M. Ballantyne Jenny Nelson Donal D. C. Bradley James R. Durrant 《Advanced functional materials》2008,18(24):4029-4035
The function of organic solar cells is based upon charge photogeneration at donor/acceptor heterojunctions. In this paper, the origin of the improvement in short circuit current of poly(3‐hexylthiophene)/6,6‐phenyl C61‐butyric acid methyl ester (P3HT/PCBM) solar cells with thermal annealing is examined. Transient absorption spectroscopy is employed to demonstrate that thermal annealing results in an approximate two‐fold increase in the yield of dissociated charges. The enhanced charge generation is correlated with a decrease in P3HT's ionization potential upon thermal annealing. These observations are in excellent quantitative agreement with a model in which efficient dissociation of the bound radical pair into free charges is dependent upon the bound radical state being thermally hot when initially generated, enabling it to overcome its coulombic binding energy. These observations provide strong evidence that the lowest unoccupied molecular orbital (LUMO) level offset of annealed P3HT/PCBM blends may be only just sufficient to drive efficient charge generation in polythiophene‐based solar cells. This has important implications for current strategies to optimize organic photovoltaic device performance based upon the development of smaller optical bandgap polymers. 相似文献
129.
Paulter N.G. Palm R.H. Barry D.D. 《Electronics Packaging Manufacturing, IEEE Transactions on》2008,31(2):150-158
The design, fabrication, and test of a wide-bandwidth (3-dB attenuation bandwidth ges 30 GHz), 50 Omega, passive coaxial probe for the electrical characterization of printed wiring board (PWB) transmission lines is described. The probe can make thousands of repeated contacts, using spring-loaded interconnects, without affecting probe performance. The probe contains an internal mechanism for dissipating static charge on the signal line of the PWB transmission line and is long enough (approximately 10 cm) to act as a transfer standard for characteristic impedance testing, as per the time-domain reflectometry test method described in IPC TM 2.5.5.7. 相似文献
130.