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41.
Combined mixtures of polymeric diphenylmethane diisocyanates (pMDI) with Urea‐formaldehyde‐resins (UF) adhesives for wood panels are shown (a) by X‐ray diffraction analysis (XRD) of the cured adhesive to present a certain percentage of microcrystallinity, this being due exclusively to the proportion of urea‐formaldehyde resin present in the mix and, (b) by polarized light optical microscopy (PLOM) to present colloidal structures in which oligomers and colloidal structures of one resin have migrated within the colloidal structures of the other resin. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2633–2636, 2007 相似文献
42.
Wet corn gluten feed (WCGF), a byproduct of the wet-milling industry, is commonly substituted in lactating dairy rations for both forages and concentrates. Previous research has shown that increasing WCGF in the diet decreased ruminal pH, likely due in part to decreasing particle size as forage inclusion rate decreased. The objective of this study was to maintain at least 10% of ration particles >19mm in length across diets while increasing WCGF inclusion in the diet. We hypothesized that as WCGF increased in this scenario, dry matter intake (DMI) and milk yield would increase and ruminal pH would be maintained. Seven ruminally cannulated, lactating Holstein cows (4 multiparous and 3 primiparous) were used in an incomplete 4×4 Latin square design. Treatments included 0, 12.4, 24.5, or 35.1% WCGF and used alfalfa hay to maintain particle size. Across treatments, crude protein and neutral detergent fiber concentrations were held relatively constant. Four 21-d periods were used with 17d of adaptation and 4d of sample collection. Indwelling ruminal pH probes were used during sampling periods and recorded pH every 5min. Particle size of total mixed rations and orts were analyzed using a Penn State Particle Separator (The Pennsylvania State University, University Park). Results were analyzed with mixed models to test the fixed effect of treatment. All diets contained ≥10% of particles >19mm; however, as WCGF increased, the proportion of particles >19mm decreased. Interestingly, with increasing WCGF, cows sorted for the particles >19mm but against particles on the bottom screen and pan. With increasing WCGF, ruminal pH was not affected, but DMI and milk yield increased in a quadratic fashion, with the peak responses for the 24.5% WCGF diet. Milk protein, lactose, and fat concentrations were not affected by treatment; however, milk protein and lactose yields increased with the inclusion of WCGF because of the increased milk yield. Production efficiency was not affected by treatments. Thus, if adequate particle size is maintained when WCGF increases in the diet, DMI and milk yield increase while maintaining production efficiency and ruminal pH. 相似文献
43.
PURPOSE: To perform a cost-utility analysis utilizing a cooperative group protocol and constrasting the results with the published quality adjusted survival. METHODS AND MATERIALS: A cost-utility analysis was performed on Radiation Therapy Oncology Group (RTOG) protocol 83-02. The quality-adjusted survival has been published previously. Pretreatment tests and chemotherapy costs are not considered, as these were similar across all treatment arms. Payor costs are calculated from Federal Register data for Medicare Region IV. Global charges are used to calculate the professional and technical charges. Costs are measured in relative value units (RVUs) and are tabulated assuming equal treatment complexity for all treatment arms. RESULTS: The number of RVUs calculated for each arm were 48 Gy--166.65; 54.4 Gy--182.17; 64.8 Gy--232.53; 72.0 Gy--272.19; 76.8 Gy--287.11; and 81.6 Gy--302.63. The RVU/QALY for the <50-year-old group were 48 Gy--119.03; 54.4 Gy--100.65; 64.8 Gy--104.78; 72.0 Gy--90.73; 76.8 Gy--193.99; and 81.6 Gy--165.37. The RVU/QALY for the >50-year-old group were 48 Gy--198.39; 54.4 Gy--276.85; 64.8 Gy--426.57; 72.0 Gy--423.71; 76.8 Gy--703.70; and 81.6 Gy--519.10. Sensitivity analysis of one treatment plan, simulation, and set of blocks for the 48 Gy and 54.4 Gy arms decreased the RVU/QALY to 105.34 and 90.05, respectively. DISCUSSION: Our analyses shows the experimental arm with the lowest RVU/QALY is also the arm with the longest quality-adjusted survival. This arm had the most efficient use of resources in this protocol. Prospective collection of all pertinent cost data is required for comparison of one treatment against another. All cooperative group protocols should have prospective quality of life and economic endpoints to allow for comparison of the most cost efficient treatment method. 相似文献
44.
PNU-151774E [(S)-(+)-2-(4-(3-fluorobenzyloxy) benzylamino) propanamide, methanesulfonate] is a structurally novel anticonvulsant having Na+ channel-blocking and glutamate release-inhibiting properties, as well as being a MAOB inhibitor. Its anticonvulsant activity was evaluated in the maximal electroshock (MES) test and in chemically induced seizures (bicuculline, BIC; picrotoxin, PIC; 3-mercaptopropionic acid, 3-MPA; pentylenetetrazole, PTZ; strychnine, STRYC). Behavioral toxicity was evaluated in the rotorod test with measurements of spontaneous locomotor activity and passive avoidance responding. The anti-MES activity of PNU-151774E in both mice and rats, respectively, produced ED50 values of 4.1 mg/kg and 6.9 mg/kg after i.p. administration or 8.0 mg/kg and 11.8 mg/kg after p.o. administration. Oral anti-MES activity in rats peaked between 1 and 2 h after administration and was evident up to 4 h. This activity was related to brain levels of unchanged drug which peaked at 37 mM within 1 h. Oral ED50 values (mg/kg) effective in blocking tonic extension seizures by chemical convulsants in mice were: BIC (26.9), PIC (60.6), 3-MPA (21.5), STRYC (104.1) and PTZ (26.8). This potency was associated with high therapeutic indices relative to: MES (78.2), BIC (23.3), PIC (10.3), 3-MPA (29.1) and STRYC (6.0). No evidence of tolerance to anti-MES activity after repeated dosing was observed. PNU-151774E did not show anti-absence seizure activity as assessed by i.v. infusion of PTZ. PNU-151774E impaired spontaneous activity in rats only at the oral rotorod ED50 dose of 700 mg/kg p.o. PNU-151774E did not impair passive avoidance responding at doses up to 40 times the oral MES ED50 dose in rats. These results indicate that PNU-151774E is an anticonvulsant effective in various seizure models with a wide therapeutic window, and with a low potential to induce tolerance and locomotor or cognitive side effects. 相似文献
45.
This paper examines the potential reliability implications of using LIGA components in communication networks. In particular,
it focuses on fibre optic-based systems and the reliability issues that need to be addressed if LIGA technology is to become
an integral part in the development of Passive Optical Networks (PONs). The paper briefly describes a typical PON configuration,
gives a basic overview of the concepts used to assess system reliability and discusses the importance of accelerated testing
and computer modelling to predict system performance.
Received: 25 August 1997 / Accepted: 30 October 1997 相似文献
46.
Abstract Electrospinning can be applied to renewables creating new materials and applications. We have utilized electrospinning in an attempt to create nanofibers from condensed tannins as well as from binary conjugates formed between this tannin with zein protein. While attempts to directly electrospin pine bark tannin extract proved unsuccessful, combining zein with this tannin gave electrospun fiber from acetic acid and dimethyl formamide (DMF) solutions. To achieve nanofibers possessing significant tannin content, high solids content (≥35%) in DMF solution was required. Electrospun nanofibers (200–400 nm dia.) could be created from zein-tannin combinations with up to 80% tannin content and appropriate solution solids content. Nanofibers could be produced from pre-formed tannin-zein conjugates or via their direct combination as a mixture in the spinning solution. Analysis of thermal stability shows the zein-tannin conjugates have similar thermal properties and stability to zein, being stable up to 240°C. 相似文献
47.
Compared the Job Choice Exercise (JCE) and the multiple choice version of the Miner Sentence Completion Scale (MSCS) by collecting data from 113 undergraduate management students, 31 campus leaders, and 28 campus nonleaders. Results show that the JCE and the MSCS were not significantly correlated and appear to measure attributes, both of which have been labeled "managerial motivation." (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
Algorithms are presented in this paper for the accurate determination of voltages, currents, and power flows in faulted three-phase unbalanced nonradial power distribution systems. The calculation of steady-state fault currents begins from a converged power flow solution and uses generalized models for all power system components. These component models are formulated using a linear graph theory approach to network modeling. The linear graph modeling techniques are extended to form an admittance matrix system model. The three-phase source and load models that are used are based on an extension of the traditional models used to represent these elements in fault studies using symmetrical components. The distribution system model consisting of sources, loads, lines, transformers, and other components is modified to account for the fault and solved to yield the line-to-neutral voltages at each bus in the faulted distribution system. The faulted system current and power flows are determined using these voltages. The results obtained using the proposed modeling approach on a system provided by a local industry are compared with the results obtained from an existing classical three-phase fault analysis algorithm, and conclusions are drawn based on these comparisons 相似文献
49.
The degree of resin cure achievable in urea formaldehyde (UF) resin is known to influence the hydrolytic stability of UF resin. In the current study, a significant difference in water extractable resin components has been observed between cured pure resin and that from medium density fiberboard (MDF) panels. Results show some 50 to 70% of resin components may be removed on water extraction from resinated MDF fiber and panel samples. In contrast, cured pure UF resins have only a small fraction of resin mass extractable into water with nitrogen-containing components remaining incorporated into the cured resin. The relatively high resin mass losses from panel material together with loss of nitrogen-containing components suggest not only free urea, but urea-methylene species are labile and readily extractable into water. Wax contributes to differing panel extractability when pressed at either 100 or 160°C, whereas panel resin loading has a significant effect on extractable resin components. A lower resin loading led to relatively greater resin extractability, which was corroborated by the extractability of resin-fiber mixtures up to 50% resin content. An assessment of extracted panel residues suggests a relative decrease of urea and urea-formaldehyde condensation products after water extraction. With UF resin highly mobile on fiber during MDF manufacture, the results suggest resin components may separate, leading to their incomplete incorporation into a cured, cross-linked UF resin matrix, with an implication that resin cure on fiber may not be complete compared to that found with pure resin. 相似文献
50.