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71.
日立金属公司开发出了一种能用于与欧州统一规格 《微电子技术》2001,29(1):28
日立金属公司开发出了一种能用于与欧州统一规格 (GSM)相对应的双带携带电话用的 6 750形状的天线开关组件。本产品是一种内含介质滤波器、天线开关、分波器且集成度较高的GSM双带相对应的小型 (6 7×5 0× 1 85mm)天线开关组件。在 90 0MHz带与 180 0MHz带 2个频带自动转换的同时 ,它是一种能够收发自动转换的高功能元件 ,衬底安装面积 ,与由分立部件构成的场合相比 ,大约可减少到 1 4 ,实现了小型化。传输带 1 2dBtyp (1 6dBmax)插入损失低 ,30dBtyp (2 5dBmin)带宽则外衰减量大。该公司计划 2 0 0 0… 相似文献
72.
73.
Noirot IC Brittan-Powell EF Dooling RJ 《The Journal of the Acoustical Society of America》2011,129(6):3445-3448
Auditory brainstem responses (ABRs) were recorded in adult budgerigars, canaries, and zebra finches in quiet and in three levels of white noise for tone stimuli between 1 and 4 kHz. Similar to behavioral results, masked ABR thresholds increased linearly with increasing noise levels. When the three species are considered together, ABR-derived CRs were higher than behavioral CRs by 18-23 dB between 2 and 4 kHz and by about 30 dB at 1 kHz. This study clarifies the utility of using ABRs for estimating masked auditory thresholds in natural environmental noises in species that cannot be tested behaviorally. 相似文献
74.
Chakhalian J Rondinelli JM Liu J Gray BA Kareev M Moon EJ Prasai N Cohn JL Varela M Tung IC Bedzyk MJ Altendorf SG Strigari F Dabrowski B Tjeng LH Ryan PJ Freeland JW 《Physical review letters》2011,107(11):116805
Using resonant x-ray spectroscopies combined with density functional calculations, we find an asymmetric biaxial strain-induced d-orbital response in ultrathin films of the correlated metal LaNiO3 which are not accessible in the bulk. The sign of the misfit strain governs the stability of an octahedral "breathing" distortion, which, in turn, produces an emergent charge-ordered ground state with an altered ligand-hole density and bond covalency. Control of this new mechanism opens a pathway to rational orbital engineering, providing a platform for artificially designed Mott materials. 相似文献
75.
Infante IC Juraszek J Fusil S Dupé B Gemeiner P Diéguez O Pailloux F Jouen S Jacquet E Geneste G Pacaud J Íñiguez J Bellaiche L Barthélémy A Dkhil B Bibes M 《Physical review letters》2011,107(23):237601
In multiferroic BiFeO(3) thin films grown on highly mismatched LaAlO(3) substrates, we reveal the coexistence of two differently distorted polymorphs that leads to striking features in the temperature dependence of the structural and multiferroic properties. Notably, the highly distorted phase quasiconcomitantly presents an abrupt structural change, transforms from a standard to a nonconventional ferroelectric, and transitions from antiferromagnetic to paramagnetic at 360±20 K. These coupled ferroic transitions just above room temperature hold promises of giant piezoelectric, magnetoelectric, and piezomagnetic responses, with potential in many applications fields. 相似文献
76.
Chen YL Sinha C Chen IC Liu KL Chi Y Yu JK Chou PT Lu TH 《Chemical communications (Cambridge, England)》2003,(24):3046-3047
Octahedral Os(II) complexes 1-5 with formula [Os(CO)3X(dbm)] are prepared through utilization of both solid-state pyrolysis and ligand exchange reactions. These complexes exhibit prominent 3pi-pi* phosphorescence with unusually long lifetimes (29-64 micros) and high quantum yields (0.08-0.13). 相似文献
78.
Sperb F Werlang IC Margis-Pinheiro M Basso LA Santos DS Pasquali G 《Applied biochemistry and biotechnology》2011,165(2):652-665
Erythropoietin (EPO) is a hormone belonging to a group of hematopoietic growth factors that control the proliferation and
differentiation of bone marrow cells. It induces the production of erythrocytes, thereby increasing the amount of circulating
hemoglobin and oxygen. Previous attempts to transgenically express human EPO in plants failed to succeed because the plants
exhibited abnormal morphology and infertility. In the present work, we describe the generation of fertile transgenic tobacco
plants able to express a synthetic version of human EPO. A 582-bp fragment of the human EPO gene was synthesized using a PCR-based
method and ligated into pCR-Blunt. After sequencing, the human EPO fragment was transferred to pWUbi.tm1 and the expression
cassette was then transferred to the binary vector pWBVec4a. After Agrobacterium-mediated transformation of Nicotiana tabacum SR1 plants, integration of the transgene into T0 and T1 plant genomes was confirmed by PCR. The human EPO gene was found to be expressed in tobacco leaves at the mRNA and protein
levels. Self-crossing allowed us to obtain T1 plants exhibiting Mendelian segregation of the transgene. None of the plants presented any kind of malformation or deformity. 相似文献
79.
Chen DY Cheng KY Ho ML Wu IC Chung MW Fu H Chou PT 《Chemical communications (Cambridge, England)》2011,47(3):985-987
A bifunctional compound 1 was designed and synthesized, in which the donor-π-conjugated-acceptor-cyanoacrylic acid configuration is suited for DSSC, while the tetraoxa-azacrown (donor) part also acts as the recognition unit for e.g. Ca(2+) and the output of DSSC is utilized as signal transduction, demonstrating a new recognition concept using DSSC. 相似文献
80.
Reis FS Pereira E Barros L Sousa MJ Martins A Ferreira IC 《Molecules (Basel, Switzerland)》2011,16(6):4328-4338
The use of natural products isolated from mushrooms, included inedible species, against infection, cancer diseases and other oxidative-stress related diseases is one of the cornerstones of modern medicine. In the present work, the antioxidant molecule profiles of inedible mushroom species were evaluated and compared with those of edible species. The order of antioxidant abundance found in inedible wild mushrooms was: phenolics > flavonoids > ascorbic acid > tocopherols > carotenoids, similar to that of edible species. Furthermore the same energetic biomolecules were found including the disaccharide trehalose, the monosaccharide alcohol derivative mannitol and the fatty acids palmitic, oleic and linoleic acids. Fomitopsis pinicola revealed a very high phenolics concentration (388 mg GAE/g extract) and powerful antioxidant properties, mainly reducing power (EC??) value 60 μg/mL similar to the standard Trolox?). It could find applications in the prevention of free radical-related diseases as a source of bioactive compounds. 相似文献