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排序方式: 共有1323条查询结果,搜索用时 343 毫秒
1.
Chenhui Ding Marion Breunig Jana Timm Roland Marschall Jürgen Senker Seema Agarwal 《Advanced functional materials》2021,31(49):2106507
Covalent organic frameworks (COFs) show advantageous characteristics, such as an ordered pore structure and a large surface area for gas storage and separation, energy storage, catalysis, and molecular separation. However, COFs usually exist as difficult-to-process powders, and preparing continuous, robust, flexible, foldable, and rollable COF membranes is still a challenge. Herein, such COF membranes with fiber morphology for the first time prepared via a newly introduced template-assisted framework process are reported. This method uses electrospun porous polymer membranes as a sacrificial large dimension template for making self-standing COF membranes. The porous COF fiber membranes, besides having high crystallinity, also show a large surface area (1153 m2 g−1), good mechanical stability, excellent thermal stability, and flexibility. This study opens up the possibility of preparation of large dimension COF membranes and their derivatives in a simple way and hence shows promise in technical applications in separation, catalysis, and energy in the future. 相似文献
2.
Tested the ability of 4 adult male Sprague-Dawley rats to use odors in discrimination among littermates living as a group. Ss were trained in a Y-maze to discriminate the presence of a littermate from its absence. Results from transfer of training in 3 subsequent testing periods indicated that the animals were capable of distinguishing among individuals when relatedness and familiarity were held constant, that this ability was not due to training, and that performance was based solely on odor cues. Results suggest that laboratory rats exhibit odor sensitivities conmensurate with very complex social processes. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
Hovius Marjolijn; Kellenbach Marion L.; Graham Kim S.; Hodges John R.; Patterson Karalyn 《Canadian Metallurgical Quarterly》2003,17(1):100
The authors investigated the impact of semantic knowledge on visual object analysis by assessing the performance of patients with semantic dementia on a different-views object matching test and on 2 object decision tests differing, for example, in whether the nonreal items were nonsense objects or chimeras of 2 real objects. On average, the patients scored normally on both the object matching and the object decision test including nonsense objects but were impaired on the object decision test including chimeras; this latter was also the only visual object test that correlated significantly with degree of semantic impairment. These findings demonstrate that object decision is not a single task or ability and that it is not necessarily independent of conceptual knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Koenen Karestan C.; Stellman Jeanne Mager; Stellman Steven D.; Sommer John F. Jr. 《Canadian Metallurgical Quarterly》2003,71(6):980
Risk factors affecting the course of posttraumatic stress disorder (PTSD) are poorly understood. As part of a larger study on characterizing exposure to herbicides in Vietnam, the authors investigated this issue in a random sample of 1,377 American Legionnaires who had served in Southeast Asia during the Vietnam War and were followed over a 14-year period. High combat exposure, perceived negative community attitudes at homecoming, minority race, depression symptoms at Time 1, and more anger at Time 1 predicted a more chronic course. Community involvement at Time 1 was protective and associated with decreased risk at Time 2. Discomfort in disclosing Vietnam experiences was associated with an increased risk for developing PTSD but did not predict its course. Combat exposure predicted PTSD course more strongly than any other risk factor. Findings suggest recovery from PTSD is significantly influenced by perceived social support. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
General issues relating to the use of outcome and process data from the treatment of antisocial children to predict future childhood adjustment are examined. For outcome measures, it was assumed that variables based on direct observation of child behavior would provide a better predictor of long-term adjustment than would ratings by participant adults. Long-term adjustment measures consisted of police arrest and out-of-home placement data collected 2 years after treatment termination. Observation data collected at termination predicted future police arrest, but parent and teacher ratings did not. It was also hypothesized that measures of the processes thought to produce the changes in child antisocial behavior would serve as predictors of future adjustment. The data supported this hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Tsai Jeanne L.; Miao Felicity F.; Seppala Emma; Fung Helene H.; Yeung Dannii Y. 《Canadian Metallurgical Quarterly》2007,92(6):1102
Previous studies have found that in American culture high-arousal positive states (HAP) such as excitement are valued more and low-arousal positive states (LAP) such as calm are valued less than they are in Chinese culture. What specific factors account for these differences? The authors predicted that when people and cultures aimed to influence others (i.e., assert personal needs and change others' behaviors to meet those needs), they would value HAP more and LAP less than when they aimed to adjust to others (i.e., suppress personal needs and change their own behaviors to meet others' needs). They test these predictions in 1 survey and 3 experimental studies. The findings suggest that within and across American and Chinese contexts, differences in ideal affect are due to specific interpersonal goals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
About Sulfur Containing Glycosides of Rape Seeds – Analysis by Thermospray Technique/Mass Spectrometry The HPLC is the method of choise for the estimation of glucosinolates occurring in rape seeds. But in comparison to GC a disadvantage is that the HPLC fractions can't be analyzed by MS directly. Such possibility is opened now with the thermospray technique. It allows to introduce the HPLC fractions immediately into the mass spectrometer system. Based on the first application of this technique to glucosinolates published by Mellon et al. (1987) the fundamentals of the thermospray technique/mass spectrometry are presented, the experimental details are explained and the characteristic ions of the thermospray mass spectra of 12 glucosinolates (desulfo derivatives) are discussed. The analytical performance of the method is examined also. 相似文献
8.
Watson Jeanne C.; Gordon Laurel B.; Stermac Lana; Kalogerakos Freda; Steckley Patricia 《Canadian Metallurgical Quarterly》2003,71(4):773
This study compared process-experiential and cognitive-behavioral psychotherapy in the treatment of major depression in a researcher allegiance-balanced randomized clinical trial. Sixty-six clients participated in weekly sessions of psychotherapy for 16 weeks. Clients' level of depression, self-esteem, general symptom distress, and dysfunctional attitudes significantly improved in both therapy groups. Clients in both groups showed significantly lower levels of reactive and suppressive coping strategies and higher reflective coping at the end of treatment. Although outcomes were generally equivalent for the 2 treatments, there was a significantly greater decrease in clients' self-reports of their interpersonal problems in process-experiential than cognitive-behavioral therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
The cooling power of aqueous solutions of ethylene oxide-propylene oxide copolymers are studied with a silver standard sample by using two apparatuses quench with injection and quench with agitation. For temperature T>400°C, the viscosity plays the predominant role; for T<400°C, the cooling is controlled by the polymer precipitation and the cooling rate decreases by lowering the cloud point of the polymer solution. This work demonstrates the possibility of adjusting the cooling curves by taking into account the thermodynamical properties of the polymer. 相似文献
10.
Discusses the nature of autonomy and explores how autonomy as a therapeutic goal relates to clinical practice and the conduct of psychotherapy. Autonomy has been defined as the power to determine one's own best interests, and it has been criticized for promoting selfishness and reflecting upper-class values and gender bias. It is suggested that issues of autonomy are involved in the process of psychotherapy as well as its aim. In therapy, there is a dynamic tension between the principle of autonomy, the right of clients to determine their own interests, and the principle of beneficence, the therapist's obligation to protect the client's welfare. Whether autonomy is an appropriate ideal in psychotherapy for women or for men is considered. Feminist theorists have criticized aspects of masculine autonomy, contrasting it with feminine relatedness; however, the idealization of relatedness is questioned. It is concluded that the present conceptualizations of autonomy do not fully encompass the complexity of human interaction. It is argued that (a) autonomy and relatedness are not essential aspects of male and female nature but depend on power and status and (b) without social change, autonomy may not be a realistic goal of therapy for women. (46 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献