摘要：To meet the requirements of the low power Zigbee system, VCO design optimizations of phase noise, power consumption and frequency tuning are discussed in this paper. Both flicker noise of tail bias transistors and up-conversion of flicker noise from cross-coupled pair are reduced by improved self-switched biasing technology, leading to low close-in phase noise. Low power is achieved by low supply voltage and triode region biasing. To linearly tune the frequency and get constant gain, distributed varactor structure is adopted. The proposed VCO is fabricated in SMIC 0.18-#m CMOS process. The measured linear tuning range is from 2.38 to 2.61 GHz. The oscillator exhibits low phase noise of-77.5 dBc/Hz and -122.8 dBc/Hz at l0 kHz and 1 MHz offset, respectively, at 2.55 GHz oscillation frequency while dissipating 2.7 mA from 1.2 V supply voltage, which well meet design specifications.

摘要：Three-dimensional(3 D)gravitational and magnetic exploration is performed using aerial measurement tools,however,this has difficulties with measuring-height design and the construction of a joint-interpretation *** present,the height in such experiments is set according to the measurement scale,and the distribution characteristics of anomalies are not fully ***,we present the idea of using the attenuation characteristics of a singular-value spectrum to evaluate the contributions of various measurement heights and multi-height combinations for inversion to correctly and reasonably design appropriate measuring heights and the number of various measurement heights to be *** jointgradient Euler-deconvolution method can accurately obtain the distribution of geological bodies from 3 D gravitational and magnetic data at an improved resolution,and experimental tests confirm these ***,an actual 3 D aeromagnetic-data-acquisition and inversion test were carried out in the vicinity of the Zhurihe Iron Mine in Inner *** fl ight-height diff erence was set to 60 m,and the specifi c distribution of lodes was obtained by the joint-gradient Euler-deconvolution *** provides a reliable basis for future detailed exploration and proves that the methods presented in this paper have good practicalapplication eff ects and prospects.

摘要：The photocatalytic decomposition of water to produce hydrogen is an important process,through which solar energy can be converted to chemical ***-precious metal phosphides have quietly attracted attention as an emerging inexpensive *** this study,we reported that a CoP/CeVO4 hybrid photocatalyst exhibited high hydrogen evolution efficiency owing to EY(eosin Y)sensitization under visible light irradiation for the first time,and the amount of generated hydrogen reached 444.6μmol in 5 *** CoP/CeVO4 nanohybrids were synthesized by a simple chemical precipitation *** coupling of CoP and CeVO4 with ZIF-9 as a precursor could be completed in one *** CeVO4 particles were firmly attached to the surface of the CoP particles to form a"small point"to"big point"*** results of X-ray diffraction,X-ray photoelectron spectroscopy,scanning electron microscopy,EDX,and transmission electron microscopy showed the formation of CoP and CeVO4 nanoparticles and the structure of the *** on a detailed analysis of the Mott-Schottky plot,the UV-vis diffuse reflectance spectra,photocurrent-time(it)curve,Tafel curve,Nyquist curve(EIS),linear volt-ampere curve(LSV),and steady-state fluorescence spectra were *** time-resolved photoluminescence measurements indicated that the reason for the high-efficiency hydrogen evolution of CoP/CeVO4 was that the bands of CoP and CeVO4 were bent due to the existence of the Schottky barrier,and a heterojunction was formed between CoP and CeVO4,which generated an internal electric field and accelerated the charge *** addition,the synergistic effect between CoP and CeVO4 provided a new hydrogen-evolution activity center for each of *** improved carrier separation efficiency and the decrease in the photo-generated recombination rate led to the excellent photocatalytic hydrogen-evolution activity of the CoP/CeVO4 composite *** work provides a new strategy for modulating the el

摘要：Rice(Oryza sativa)spikelets are a unique inflorescence structure and their development directly determines grain size and *** many genes related to spikelet development have been reported,the molecular mechanisms underlying this process have not been fully *** this study,we identified a new recessive rice mutant,lacking rudimentary glume 1(lrg1).The lrg1 spikelets only formed one rudimentary glume,which,along with the sterile lemmas,was homeotically transformed into lemma-like organs and acquired lemma *** transition from the spikelet to the floral meristem was delayed in the lrg1 mutant,resulting in the formation of an ectopic lemma-like organ between the sterile lemma and the terminal *** addition,we found that the abnormal lrg1 grain phenotype resulted from the alteration of cell numbers and the hull ***1 encodes a ZOS4-06-C2H2 zinc-finger protein with the typical EAR motifs,and is expressed in all organs and ***1 localizes to the nucleus and can interact with the TOPLESS-RELATED PROTEINs(TPRs)to repress the expressions of their downstream target *** together,our results reveal that LRG1 plays an important role in the regulation of spikelet organ identity and grain size.

摘要：依据药效团的拼合策略,以上市药瑞巴派特为先导化合物,设计并合成了一系列具有苯丙烯酰氨基酸结构化合物,其结构均经1H NMR、13C NMR和MS确证.用Elisa法测定目标化合物对LPS诱导的RAW264.7细胞释放IL-6和TNF-α的抑制活性.结果显示所设计化合物显示出良好的抑制活性,其中有4个化合物的活性明显优于瑞巴派特.

摘要：This paper addresses the gas path component and sensor fault diagnosis and isolation(FDI) for the auxiliary power unit(APU). A nonlinear dynamic model and a distributed state estimator are combined for the distributed control system. The distributed extended Kalman filter(DEKF)is served as a state estimator,which is utilized to estimate the gas path components’ flow capacity. The DEKF includes one main filter and five sub-filter groups related to five sensors of APU and each sub-filter yields local state flow capacity. The main filter collects and fuses the local state information,and then the state estimations are feedback to the sub-filters. The packet loss model is introduced in the DEKF algorithm in the APU distributed control architecture. FDI strategy with a performance index named weight sum of squared residuals(WSSR) is designed and used to identify the APU sensor fault by removing one sub-filter each time. The very sensor fault occurs as its performance index WSSR is different from the remaining sub-filter combinations. And the estimated value of the soft redundancy replaces the fault sensor measurement to isolate the fault measurement. It is worth noting that the proposed approach serves for not only the sensor failure but also the hybrid fault issue of APU gas path components and sensors. The simulation and comparison are systematically carried out by using the APU test data,and the superiority of the proposed methodology is verified.

摘要：With the continuous development of full tensor gradiometer （FTG） measurement techniques, three-dimensional （3D） inversion of FTG data is becoming increasingly used in oil and gas exploration. In the fast processing and interpretation of large-scale high-precision data, the use of the graphics processing unit process unit （GPU） and preconditioning methods are very important in the data inversion. In this paper, an improved preconditioned conjugate gradient algorithm is proposed by combining the symmetric successive over-relaxation （SSOR） technique and the incomplete Choleksy decomposition conjugate gradient algorithm （ICCG）. Since preparing the preconditioner requires extra time, a parallel implement based on GPU is proposed. The improved method is then applied in the inversion of noise- contaminated synthetic data to prove its adaptability in the inversion of 3D FTG data. Results show that the parallel SSOR-ICCG algorithm based on NVIDIA Tesla C2050 GPU achieves a speedup of approximately 25 times that of a serial program using a 2.0 GHz Central Processing Unit （CPU）. Real airbome gravity-gradiometry data from Vinton salt dome （south- west Louisiana, USA） are also considered. Good results are obtained, which verifies the efficiency and feasibility of the proposed parallel method in fast inversion of 3D FTG data.

摘要：The current literature lacks uniform calculation methods for following trajectory control for autonomous vehicles,including the calculation of errors,determination of tracking points,and design of feedforward ***,a complete calculation method is proposed to address this ***,a control equation in the form of an error is obtained according to the dynamic equation of the vehicle coordinate system and the trajectory following ***,the deviation of the vehicle state is obtained according to the current vehicle s state and the following control ***,a linear quadratic regulator(LQR)controller with feedforward control is designed according to the characteristics of the dynamic *** the proposed LQR,the simulation of computational time,anti-interference,and reliability analysis of the trajectory following control is performed by programming using *** simulation outcomes are then compared with the experimental results from the *** comparison indicates that the proposed complete calculation method is effective,reliable,and capable of achieving real-time and anti-interference following control *** simulation results with or without feedforward control show that the steady-state error is eliminated and that good control performance is obtained by introducing feedforward control.

摘要：Cognitive radio is considered as an efficient way to improve the spectrum efficiency. As one of its key technologies,spectrum handoff can guarantee the transmission continuity of secondary users(SUs). In this paper,we address a new and more generalized spectrum handoff problem in cognitive radio networks(CRNs),by considering simultaneously energy efficiency,multiple spectrum handoffs and multiple channels. Furthermore,effects of the primary users'(PUs')arrival and service rate on the target channel sequence selection are also considered. In order to obtain the energy-efficient target channel sequence,we firstly analyze the energy consumption and the number of delivered bits per hertz in the spectrum handoff process,and formulate a ratio-type energy efficiency optimization problem,which can be transformed into a parametric problem by utilizing fractional programming. Then,we propose an algorithm combining dynamic programming with bisection(DPB)algorithm to solve the energy efficiency optimization problem. Our simulation results verify that the designed target channel sequence has better performance than the existing algorithms in terms of energy efficiency.

摘要：Natural chromophores wildly exist in living bodies and have been utilized for thousands of years[1].Many of them,such as quinine[2],luciferin[3-5],coelenteramide[6,7],and coumarin[8],can fluoresce and have been widely applied in biosensor,immune sensor,and fluorescent imaging agents[9,10].