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1.
A modifying influence of ortho-cresol (o-cresol) on the carcinogenic effect of benzo(a)pyrene (B(a)P) in their combined peroral administration to CC57Br mice has been revealed. During the simultaneous administration of the o-cresol (1 mg) and B(a)P (1 mg) the rate of tumours, their multiplicity index, the degree of malignancy increased and the latent period shortened. In case of o-cresol administration before or after B(a)P (in the same doses) the decrease of carcinogenic effect has been revealed. In case of simultaneous administration of 10 mg of the o-cresol and 5 mg of the B(a)P the tumor incidence did not change in comparison with the animals of the control group which received only B(a)P. But their progression was hampered which was confirmed by a decrease of the malignancy rate, frequent occurrence and prolongation of the period of the malignization beginning.  相似文献   

2.
A 256-Mb SDRAM (245.7 mm2) has been developed using (1) a high cell occupation ratio (60.2%) array design for chip size reduction and a high yield, (2) a prefetched pipeline scheme (PPS) using a first-in first-out (FIFO) buffer with parallel serial converter for 250-MHz clock frequency operation, and (3) a synchronous mirror delay (SMD) circuit for 2.5-ns clock access and low standby current  相似文献   

3.
非对称多模量子叠加态光场的等幂高次和压缩   总被引:1,自引:0,他引:1  
根据量子力学中的态叠加原理,构造了由多模复共轭相干态|{zj(a)*}>q和多模复共轭相干态|{zj(b)*}>q的相反态|{-zj(b)*}>q的线性叠加所组成的非对称两态叠加多模量子叠加态光场|ψ(2)>q,利用多模压缩态理论研究了态|ψ1f(2)>q的等幂高次和压缩特性,结果表明: 1)当Rj(a)=Rj(b)和ψj(a)-ψj(b)=±(2k 1)π(k=0,1,2,3……),态|ψ1f(2)>q的两个正交相位分量均处于N-H最小测不准态的结果;2)当Rj(a)=Rj(b)=Rj和ψj(a)=ψj(b)=ψj,ψ态|1f(2)>q的等幂高次和压缩与文献3的结果相似; 3)当Rj(a)≠Rj(b)=Rj和ψj(a)=ψj(b)=ψj,且和满足一定条件时,无论qN为奇数还是偶数,态|ψ1f(2)>q的两个正交相位分量均可分别呈现周期性变化的等幂高次和压缩效应,但qN为奇数时的压缩深度大于qN为偶数时的压缩深度。  相似文献   

4.
以Zr0 .8Sn0 .2 TiO4 作为主配方 ,以ZnO ,La2 O3,Fe2 O3和NiO作为改性剂 ,采用传统陶瓷制备工艺 ,对其进行了掺杂改性的初步探索。在优选的配方和工艺条件下 ,得到Zr0 .8Sn0 .2 TiO4 添加0 .5wt%ZnO(即质量分数为 0 .5 %的ZnO)的相对介电常数εr≈ 33.2 31,品质因数Q≈ 5 5 2 8(7GHz) ;添加 0 .5wt %ZnO ,0 .5wt?2 O3和 0 .2wt%NiO ,其εr≈ 33.73,Q≈ 5 2 5 4(7GHz) ;添加 1wt%ZnO和 0 .5wt %La2 O3,材料的εr≈ 37.996 ,Q≈ 4 72 3(7GHz)。  相似文献   

5.
Gallium arsenide (GaAs) films were grown by molecular beam epitaxy (MBE) on a (511) silicon substrate and a compliant (511) silicon-on-insulator (SOI) substrate. The top silicon layer of the compliant (511) SOI was thinned to ~1000 Å. The five inch diameter SOI wafer was created by wafer bonding. The GaAs (004) x-ray diffraction (XRD) reflection showed a 25% reduction in the full width half maximum (FWHM) for GaAs on a compliant (511) SOI as compared to GaAs on a silicon substrate. Cross section transmission electron microscopy (XTEM) clearly indicates a different dislocation structure for the two substrates. The threading dislocation density is reduced by at least an order of magnitude in the compliant (511) SOI as compared to the (511) silicon. XTEM found dislocations and damage was generated in the top silicon layer of the compliant SOI substrate after GaAs growth.  相似文献   

6.
A new method is proposed for preparing plan-view specimens of a CeO(2)/Gd(2)Zr(2)O(7) multilayer on a metal substrate using focused ion beam milling. In the plan-view specimen, a membrane from the surface region of the CeO(2) to the Gd(2)Zr(2)O(7) layer was thinned to electron transparence so that the entire span of the multilayer can be observed in a single sample. The in-plane alignments of the CeO(2) layer and the Gd(2)Zr(2)O(7) layer were analysed using selected-area diffraction patterns (SADPs). The boundaries between the CeO(2) grains were also examined using SADPs.  相似文献   

7.
采用超声分子束技术,以飞行时间(TOF)质谱仪,于410-371nm内,在不同能量的激光作用下,着重检测了气相Si(CH3)4分子在15个波长点处的多光子电离(MPI)TOF质谱分布。根据实验结果,讨论了Si(CH3)4可能的MPI机理,得到了Si^ 主要来自于母体分子及中性碎片的多光子解离-硅原子的共振电离、Si(CH3)n^ (n=1,2,3)主要来自于中性碎片Si(CH3)n(n=1,2,3)的自电离、而Si(CH3)4^ 则来自于母体分子的(3+1)电离的结论。  相似文献   

8.
The crystal and defect structures of coarse-grained crystals of La(2/3-x)Li(3x)TiO3 grown from the melt by the Tammann-St?ber method were studied by transmission electron microscopy and powder X-ray diffraction. The as-grown crystals of La(2/3-x)Li(3x)TiO3 have a Li-poor composition of La(0.57)Li(0.29)TiO3 and a diagonal-type unit cell of 2(1/2)a(p) x 2(1/2)a(p) x 2a(p) with the tetragonal symmetry [space group: P4/nbm (#125)] due to both the La-cation ordering and the tilting of TiO6 octahedra. The secondary La2Ti2O7 phase precipitates in the form of plates in the La(2/3-x)Li(3x)TiO3 phase with the orientation relationships of 001(p)//[100](La2Ti2O7) and {110}(p)//(001)(La2Ti2O7), which may cause detrimental effects to ionic conductivity.  相似文献   

9.
Recently, a new approach has been proposed to estimate insulin sensitivity (S(I)) from an oral glucose tolerance test or a meal using an "integral equation". Here, we improve on the "integral equation" by resorting to a "differential equation" approach. The classic glucose kinetics minimal model was used with the addition of a parametric model for the rate of appearance into plasma of oral glucose (Ra). Three behavioral models of Ra were proposed: piecewise-linear (P), spline (S) and dynamic (D). All three models performed satisfactorily allowing a precise estimation of S(I) and a plausible reconstruction of Ra. Mean S(I) estimates were virtually identical: S(I)P = 6.81 +/- 0.87 (SE); S(I)S = 6.53 +/- 0.80; and S(I)D = 6.62 +/- 0.79. S(I) strongly correlated with the integral-equation index (I) S(I)I: r = 0.99, p < 0.01 for models D and S, and r 0.97, p < 0.01 for P. Also, SI compared well with insulin sensitivity estimated from intravenous glucose tolerance test in the same subjects (r = 0.75, p < 0.01; r = 0.71, p < 0.01; r = 0.73, p < 0.01, respectively, for P, S, and D models versus s(I)IVGTT). Finally, the novel approach allows estimation of SI from a shorter test (120 min): model P yielded S(I)R = 7.16 +/- 1.0 (R for reduced) which correlated very well with S(I)P and S(I)I (respectively, r = 0.94, p < 0.01; r = 0.95, p < 0.01) and still satisfactorily with S(I)IVGTT (r = 0.77, p < 0.01).  相似文献   

10.
A signal remodulation scheme of 10-Gb/s differential phase-shift keying(DPSK) downstream and 10-Gb/s on-off keying(OOK) upstream using a semiconductor optical amplifier(SOA) and a Mach-Zehnder intensity modulator(MZ-IM) at the optical networking unit(ONU) side for wavelength division multiplexed passive optical network(WDM PON) is proposed.Simulation results indicate that error-free operation can be achieved in a 20-km transmission,and the receiver sensitivity of return-to-zero differential phase-shift keying(RZ-DPSK) is higher than nonreturn-to-zero differential phase-shift keying(NRZ-DPSK) in the proposed scheme.  相似文献   

11.
Partial system triplication with a single majority vote is analysed to find (a) the region of superiority of partial triplication over total triplication and (b) over no redundancy, (c) the degree of partial triplication which maximises reliability, (d) the maximum system reliability produced by partial redundancy. Only approximate or numerical solutions to (a) and (c) have appeared previously. (b) and (d) are entirely new.  相似文献   

12.
Deep‐blue fluorescent compounds are particularly important in organic light‐emitting devices (OLEDs). A donor–accepotor (DA)‐type blue‐emitting compound, 1‐(10‐(4‐methoxyphenyl)anthracen‐9‐yl)‐4‐(10‐(4‐cyanophenyl)anthracen‐9‐yl)benzene ( BD3 ), is synthesized, and for comparison, a nonDA‐type compound, 1,4‐bis(10‐phenylanthracene‐9‐yl)benzene ( BD1 ) and a weak DA‐type compound, 1‐(10‐phenylanthracen‐9‐yl)‐4‐(10‐(4‐cyanophenyl)anthracen‐9‐yl)‐benzene ( BD2 ), are also synthesized. The twisted conformations of the two anthracene units in the compounds, confirmed by single crystal X‐ray analysis, effectively prevent π‐conjugation, and the compound shows deep‐blue photoluminescence (PL) with a high PL quantum efficiency, almost independent of the solvent polarity, resulting from the absence of an intramolecular charge transfer state. The DA‐type molecule BD3 in a non‐doped device exhibits a maximum external quantum efficiency (EQE) of 4.2% with a slight roll‐off, indicating good charge balance due to the DA‐type molecular design. In the doped device with 4,4′‐bis(N‐carbazolyl)‐1,1′‐biphenyl (CBP) host, the BD3 exhibits higher EQE than 10% with Commission International de L'Eclairge (CIE) coordinates of (0.15, 0.06) and a narrow full‐width at half‐maximum of 45 nm, which is close to the CIE of the high definition television standard blue.  相似文献   

13.
In this study, we introduce and investigate a class of neural architectures of self-organizing neural networks (SONNs) that is based on a genetically optimized multilayer perceptron with polynomial neurons (PNs) or fuzzy polynomial neurons (FPNs), develop a comprehensive design methodology involving mechanisms of genetic optimization, and carry out a series of numeric experiments. We distinguish between two kinds of SONN architectures: (a) PN-based and (b) FPN-based SONNs. The augmented genetically optimized SONN (gSONN) results in a structurally optimized structure and comes with a higher level of flexibility in comparison to the one encountered in the conventional SONN. The genetic algorithm (GA)-based design procedure being applied at each layer of SONN leads to the selection of preferred nodes (PNs or FPNs) with specific local characteristics (such as the number of input variables, the order of the polynomial, and a collection of the specific subset of input variables) available within the network.  相似文献   

14.
A novel intramolecular charge transfer (ICT) based blue fluorophor, 5,11-di(40-dimesitylboronphenyl)indolo[3,2-b]carbazole(DDBICZ), possessing a high fluorescent quantum yield of 0.52, a high triplet energy level (2.59 eV), and an intriguing bipolar charge transporting ability, was used as a highly efficient blue fluorophor and a host for a yellow phosphor. Doping a yellow phosphor(bis(2-(3-trifluoromethyl-4-fluorophenyl)-4-methylquinolyl)(acetyl-acetonate)iridium(III) (Ir(ffpmq)2(acac)) in the host DDBICZ, a simplified fluorescence/phosphorescence (F/P)-based hybrid white organic light-emitting diode (WOLED) with a symmetrical BYB-EML of DDBICZ (10 nm)/DDBICZ: 6 wt% Ir(ffpmq)2(acac) (10 nm)/DDBICZ (10 nm) is demonstrated. The hybrid WOLED exhibits excellent high color stability and good color quality. Under wide operating voltage range from 5 V to 10 V, the Commission Internationale de L'Eclairage (CIE) coordinates of the hybrid WOLED only change from (0.35, 0.36) to (0.34, 0.35), with a high color rending index (CRI) of 79–81. The high color stability is due to the fact that the BYB-EML effectively offsets the change of emission intensity from different emitters caused by the shift of carrier recombination zone with the increase of voltage. In addition, the hybrid WOLED also reveals a considerable current efficiency of 24.4 cd/A. These results demonstrate that efficient F/P hybrid WOLEDs with high color stability could be achieved by such simple BYB-EML structure using single-dopant strategy.  相似文献   

15.
In a previous paper, the authors (ibid., vol.38, pp.989-998, May 1991) clarified the operational mechanism of a charge modulation device (CMD) image sensor and confirmed that numerical calculations using the transistor analysis program for imagers calculating non-steady-state equations (TRINE) predicted the actual performance of a CMD imager within a 20% discrepancy. Following these results, the scaling-down of device dimensions and the inherent operational speed are estimated using TRINE in order to realize a future high-resolution CMD image sensor. The analysis shows that a device size of 5.0 μm (H)×5.2 μm (V) is attainable without degrading the performance of the 10.2 μm (H)×10.4 μm (V) CMD imager and that the operational speed of a CMD is fast enough for a high-definition TV (HDTV) application which requires a scan rate of several tens of nanoseconds  相似文献   

16.
A novel, membrane potential sensitive dye and a fluorescence imaging plate reader (FLIPR) have been used to characterize the pharmacological properties of rat Na(v)1.8 voltage-gated sodium channels (VGSC) in parallel with rat Na(v)1.2a and human Na(v)1.5 VGSC subtypes, respectively. The sensitivity of recombinant Na(v)1.2a-CHO, Na(v)1.5-293-EBNA, and Na(v)1.8-F-11 cells to VGSC activators was subtype dependent. Veratridine evoked depolarization of Na(v)1.2a-CHO and Na(v)1.5-293-EBNA cells with pEC(50) values of 4.78 +/- 0.13 and 4.84 +/- 0.12, respectively (n = 3), but had negligible effect on Na(v)1.8-F-11 cells (pEC(50) < 4.5). Type I pyrethroids were without significant effect at all subtypes. In contrast, the type II pyrethroids deltamethrin and fenvalerate evoked direct depolarization of Na(v)1.8-F-11 and Na(v)1.5-293-EBNA cells. Deltamethrin potentiated the veratridine-evoked response in Na(v)1.8-F-11 cells by > or =20-fold, in contrast to a 相似文献   

17.
We report the first demonstration of a dual-metal gate complementary metal oxide semiconductor (CMOS) technology using titanium (Ti) and molybdenum (Mo) as the gate electrodes for the N-metal oxide semiconductor field effect transistors (N-MOSFETs) and P-metal oxide semiconductor field effect transistors (P-MOSFETs), respectively. The gate dielectric stack consists of a silicon oxy-nitride interfacial layer and a silicon nitride (Si3N4) dielectric layer formed by a rapid-thermal chemical vapor deposition (RTCVD) process. C-V characteristics show negligible gate depletion. Carrier mobilities comparable to that predicted by the universal mobility model for silicon dioxide (SiO2) are observed  相似文献   

18.
研究了一种新型发光材料(E)-2-(2-(9H-fluoren-2-yl)vinyl)quinolato-Zinc的发光性能,利用它的空穴传输和发光特性制备了有机白光器件,器件的结构为:ITO/2T-NATA(15nm)/FHQZn(38nm)/NPB(25nm)/BCP(10nm)/Alq(30nm)/LiF(0.5nm)/Al,其中,(E)-2-(2-(9H-fluoren-2-yl)vinyl)quinoato-Zinc(FHQZn)作为空穴传输层和黄橙色发射层,N,N′-bis-(1-naphthyl)-N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine(NPBX)作为蓝光发射层。器件最大的电流效率为1.68cd/A(at7V),最大的亮度为4624cd/m2(at12V),此时色坐标为(0.28,0.25)。器件的色坐标由7V(66.83cd/m2)时的(0.27,0.29)到12V(4624cd/m2)时的(0.28,0.25)几乎不变,是一个基于新型材料的色度较稳定的有机白光器件。  相似文献   

19.
We demonstrate a standalone (no global clock) burst-mode receiver (BMRx) for a 7 times 622 Mb/s incoherent spectral-amplitude-coded optical code-division multiple-access system. The receiver provides the following functions: quantization (intensity noise filtering), clock and data recovery, burst-mode functionality (automatic phase acquisition) using a clock phase aligner (CPA), framing (for byte synchronization), and forward-error correction (FEC) using a (255, 239) Reed-Solomon decoder. The receiver provides an instantaneous (zero preamble bit) phase acquisition time for any phase step (plusmn2pi rads) between consecutive packets. With the CPA, we report a zero packet loss ratio (PLR) for up to four simultaneous users and more than a 300-fold improvement in the PLR for a fully loaded system. The BMRx also accomplishes more than 2.5 dB of coding gain, and achieves error-free (bit-error rate ) operation for a fully loaded system.  相似文献   

20.
We report on efficient solution-processed phosphorescent white polymer light-emitting diodes (WPLEDs) with tunable color-correlated temperature (CCT) and color rendering index (CRI), through rationally controlling the composition of the emission layer (EML) based on a near-infrared (NIR)-emitting dinuclear cyclometalated platinum (II) complex bridged with NˆS anionic ligand, named (niq)2Pt2(μ-C8PhOXT)2 (Pt-1, in which PhOXT is 5-(phenyl-1,3,4-oxadiazole)-2-thiol, niq is 1-naphthylisoquinolinato), a sky-blue emitter iridium (III) bis[(4,6-di-fluorophenyl)-pyridinato-N,C2] (picolinate) (FIrpic), and a yellow emitter bis[2-(thieno[3,2-c]pyridin-4-yl)phenyl]iridium(III)(acetylacetonato) (PO-01). One of the best three-color WPLEDs shows a CCT of 3246 K as well as an excellent high CRI of 87, which are greatly beneficial in reducing deep-blue light damage and simultaneously meet the requirement for good color reproduction. Meanwhile, the relevant WPLED also achieves a maximum current efficiency of 12.1 cd/A, corresponding to an external quantum efficiency of 10.6%. This work presents an effective approach through rational combination of sky-blue, yellow, and NIR emitters towards high-performance solution-processable WPLEDs with a physiologically-friendly CCT and a high CRI.  相似文献   

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