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51.
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A rapid nondestructive test method for ceramic multilayer capacitors made from piezoelectric materials such as barium titanate or lead-containing materials is described and evaluated. The test method is based on the internal excitation of standing acoustic waves in the capacitors. The standing waves are severely dampened by defects such as indentations and delaminations or warped electrodes. An undampened resonance is a good indication of a defect-free ceramic multilayer capacitor. This finding was used in a nondestructive test setup to evaluate about 1000 capacitors. Through metallographic (cross-section) examination, a sorting accuracy of 2% false accepts and 8% false rejects was determined for the highspeed test setup. The test setup has the potential to test over 100 000 capacitors an hour. [Key words: capacitors, nondestructive testing, multilayers, mechanical properties, electrical properties.]  相似文献   
53.
The authors assessed women and men who either reported continuous memories of their childhood sexual abuse (CSA, n = 92), reported recovering memories of CSA (n = 38), reported believing they harbored repressed memories of CSA (n = 42), or reported never having been sexually abused (n = 36). Men and women were indistinguishable on all clinical and psychometric measures. The 3 groups that reported abuse scored similarly on measures of anxiety, depression, dissociation, and absorption. These groups also scored higher than the control group. Inconsistent with betrayal trauma theory, recovered memory participants were not more likely to report abuse by a parent or stepparent than were continuous memory participants. Rates of depression and posttraumatic stress disorder did not differ between the continuous and recovered memory groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
54.
To evaluate and compare the efficacy of two widely used behavioral approaches for the treatment of chronic pain, 81 mildly dysfunctional chronic low back pain patients were randomly assigned to operant behavioral (OB) treatment, cognitive-behavioral (CB) treatment, or a waiting-list (WL) control condition. Both treatments, which were conducted in eight-session outpatient groups, resulted in decreased physical and psychosocial disability. The OB patients showed greater pre- to posttreatment improvement as rated by patients and their spouses than did the CB patients. Generally, the OB patients showed a leveling off in improvement at 6- and 12-month follow-ups, whereas the CB patients generally continued to improve over the 12 months following treatment. At 12-month follow-up, patients in both treatments remained significantly improved, with no significant differences between conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
55.
A pre-formed Meisenheimer complex of a naphthalenediimide (NDI) with tetrabutylammonium fluoride (TBAF) is obtained in a simple way by mixing dibrominated 4,9-dibromo-2,7-bis(2-octyldodecyl)benzo[lmn][3,8]phenanthroline-1,3,6,8(2H,7H)-tetraone and TBAF in solution and used as a dopant for n-type organic thermoelectrics. Two n-type polymers PNDIClTVT and PBDOPVTT are synthesized, n-doped, and characterized as conductive and thermoelectric materials. PNDIClTVT doped with NDI-TBAF presents a high σ value of 0.20 S cm–1, a Seebeck coefficient (S) of −1854 µV K–1, and a power factor (PF) of 67 µW m–1 K–2, among the highest reported PF in solution-processed conjugated n-type polymer thermoelectrics. Using 4-(1,3-dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)phenyl)dimethylamine and NDI-TBAF as co-dopants, PNDIClTVT has a PF > 35 µW m–1 K–2; while for PBDOPVTT σ = 0.75 S cm–1 and PF = 58 µW m–1 K–2. In this study it is found that an ionic adduct together with a neutral dopant improves the performance of n-type organic thermoelectrics leading to an enhanced power factor, and more generally, the role of such an adduct in polymer doping is also elucidated.  相似文献   
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False memory creation was examined in people who reported having recovered memories of traumatic events that are unlikely to have occurred: abduction by space aliens. A variant of the Deese/Roediger-McDermott paradigm (J. Deese, 1959; H. L. Roediger III & K. B. McDermott, 1995) was used to examine false recall and false recognition in 3 groups: people reporting recovered memories of alien abduction, people who believe they were abducted by aliens but have no memories, and people who deny having been abducted by aliens. Those reporting recovered and repressed memories of alien abduction were more prone than control participants to exhibit false recall and recognition. The groups did not differ in correct recall or recognition. Hypnotic suggestibility, depressive symptoms, and schizotypic features were significant predictors of false recall and false recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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ABSTRACT

Clenbuterol is a steroid-type drug used in respiratory treatments in both humans and animals. However, it has a secondary effect related to the hypertrophy process in muscle and fat reduction. The illegal or bad use of clenbuterol has been reported in several countries, but there is scarce information in South America, where the production and consumption of meat are considerable. In this sense, the present study aimed at evaluating the occurrence of clenbuterol in bovine muscle and liver samples from a high cattle production area of Ecuador in 2015 and 2018. For this purpose, 57–58 samples were evaluated in 2015 and 20 samples in 2018 using the Enzyme-Linked Inmuno Sorbent Assay and ultrahigh-performance liquid chromatography-tandem mass spectrometry. The results showed complained results for clenbuterol in meat samples from both years and 23% (2015) and 85% (2018) of the samples of meat complied the maximum residue level defined by CODEX.  相似文献   
60.
工艺材料中的污染物会引起器件失效并影响成品率。但对于新材料,标准的分析认证(COA)也许并不是想象中的那么可靠。  相似文献   
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