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91.
92.
The influence of different types of iron salts (i.e., ferrous or ferric cations with sulphate, nitrate or chloride anions) on the reaction between coarse thermomechanical pulp and acid hydrogen peroxide (Fenton chemistry) was studied when the initial pH was 3.2 and 5.3. Also, ferric ions chelated with EDTA or EDG at different molar ratios were compared with ferrous sulphate when the initial pH was extended from about 3 to 8. Different anions of ferric ion salt gave a similar catalytic effect. At an initial pH of 7–8, the ferric-EDTA catalyzed reaction resulted in similar or higher hydrogen peroxide consumption and more detectable hydroxyl radicals than the ferrous sulphate catalyzed reaction, but less reaction with the pulp was indicated. Between pH 5–8, using Fe-EDG as a catalyst gave higher hydrogen peroxide consumption and more detectable hydroxyl radicals than if using ferrous sulphate; however, the measured effect on the pulp was similar or less. 相似文献
93.
Lassi Koski Cecilia Ronnevi Elina Berntsson Sebastian K. T. S. Wrmlnder Per M. Roos 《International journal of molecular sciences》2021,22(22)
Amyotrophic lateral sclerosis (ALS), Alzheimer’s disease, Parkinson’s disease and similar neurodegenerative disorders take their toll on patients, caregivers and society. A common denominator for these disorders is the accumulation of aggregated proteins in nerve cells, yet the triggers for these aggregation processes are currently unknown. In ALS, protein aggregation has been described for the SOD1, C9orf72, FUS and TDP-43 proteins. The latter is a nuclear protein normally binding to both DNA and RNA, contributing to gene expression and mRNA life cycle regulation. TDP-43 seems to have a specific role in ALS pathogenesis, and ubiquitinated and hyperphosphorylated cytoplasmic inclusions of aggregated TDP-43 are present in nerve cells in almost all sporadic ALS cases. ALS pathology appears to include metal imbalances, and environmental metal exposure is a known risk factor in ALS. However, studies on metal-to-TDP-43 interactions are scarce, even though this protein seems to have the capacity to bind to metals. This review discusses the possible role of metals in TDP-43 aggregation, with respect to ALS pathology. 相似文献
94.
Effect of additives on the melt rheology and thermal degradation of poly[(R)‐3‐hydroxybutyric acid] 下载免费PDF全文
Carlos R. Arza Patric Jannasch Peter Johansson Per Magnusson Alan Werker Frans H. J. Maurer 《应用聚合物科学杂志》2015,132(15)
Thermal degradation of poly[(R)−3‐hydroxybutyric acid] (PHB) during melt mixing results in random chain scission that produces shorter polymer chains containing crotonic and carboxyl end groups. One way of preventing this serious reduction of molar mass is to add agents that react with at least two of the newly generated end groups. Different types of commercially available additives known to react with carboxyl group, namely bis(3,4‐epoxycyclohexylmethyl) adipate (BECMA), 2,2'‐bis(2‐oxazoline) (BOX), trimethylolpropane tris(2‐methyl‐1‐aziridinepropionate) (PETAP), triphenyl phosphate (TPP), tris(nonylphenyl) phosphate (TNPP), polycarbodiimide (PCDI), and poly(methyl metharylate‐co‐glycidyl methacrylate) (GMA.MMA) were mixed with PHB by cocasting from solution in chloroform. Dynamic rheology as well as measurements of molar masses before and after dynamic analysis was used to evaluate the effect of the additives on the melt stability of PHB. Measurements of the dynamic shear modulus and the molar mass of molten PHB with the additives PCDI and GMA.MMA showed a minor improvement on the thermal stability. Furthermore, TPP and TNPP did not affect the thermal stability of PHB, whereas the presence of BECMA, BOX, and PETAP gave a strong decrease of the dynamic modulus compared with neat PHB. © 2014 The Authors Journal of Applied Polymer Science Published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41836. 相似文献
95.
Based on results from eigenspace and residual assignment a closed-form parameterization of all transfer function matrices obtainable by state feedback is given. 相似文献
96.
Per Brinch Hansen 《Software》1989,19(6):553-578
This paper defines a programming language for distributed processing called Joyce. Joyce is based on CSP and Pascal. A Joyce program defines concurrent agents which communicate through synchronous channels. The agents may be recursive. 相似文献
97.
Two coupling agents based on trichloro-s-triazine with different terminal unsaturated groups were synthesized in order to improve the bonding between cellulose fibers and an unsaturated polyester matrix. The products of the reactions between hydroxyl groups of cellulose and reactive species of coupling agents were analysed by Fourier-transform infrared spectroscopy (FTIR) and by elemental microanalyses. ESCA was used for surface characterization of treated fibers. The coupling agents were found to be concentrated on the fiber surface. Polymerization of styrene was carried out in the presence of treated fibers. That the unsaturated groups of the treated fibers were able to copolymrize with styrene was shown by FTIR. Further evidence of the presence of grafted polystyrene on the surfaces of the cellulose fibers was provided by ESCA measurements. 相似文献
98.
Although effective therapies for pathological gambling exist, their uptake is limited to 10% of the target population. To lower the barriers for help seeking, the authors tested an online alternative in a randomized trial (N = 66). The participants were pathological gamblers not presenting with severe comorbid depression. A wait-list control was compared with an 8-week Internet-based cognitive behavior therapy program with minimal therapist contact via e-mail and weekly telephone calls of less than 15 min. Average time spent on each participant, including phone conversations, e-mail, and administration, was 4 hr. The Internet-based intervention resulted in favorable changes in pathological gambling, anxiety, depression, and quality of life. Composite between-group effect size (Cohen's d) at posttreatment was 0.83. Follow-ups carried out in the treatment group at 6, 18, and 36 months indicated that treatment effects were sustained (ds = 2.58, 1.96, and 1.98). This evidence is in support of Internet-delivered treatment for pathological gamblers. However, it is not clear how effective the treatment is for more severely depressed individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
Observed parental interactive patterns in the presence (a triadic setting) and in the absence (a dyadic setting) of the spouse in 44 families with 16 female and 28 male early adolescents (approximately 13 yrs old). Findings indicate that in accordance with hypotheses, the presence of the father enhanced the quality of mother–son relations, whereas the presence of the mother reduced the quality of father–son relations. The presence of the spouse influenced the extent to which parents treated girls and boys differently: Mothers differentiated more between girls and boys in the presence of the spouse, whereas fathers differentiated more between girls and boys in the absence of the spouse. Relative to the dyad, parental role differentiation increased in the triad but only in families of boys. In demonstrating interdependencies among family relationships and the responsivity of parental behaviors to the interpersonal structure of interaction settings, the results support a systems model of family processes. Implications for the study of family relations and sex typing at early adolescence are discussed. (60 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.