Temperature-insensitive reading of a flash memory cell

The temperature characteristics of the read current of the NOR embedded flash memory with a 1.5T-per-cell structure are theoretically analyzed and experimentally verified.We verify that for a cell programmed with a“10”state,the read current is either increasing,decreasing,or invariable with the temperature,essentially depending on the reading overdrive voltage of the selected bitcell,or its programming strength.By precisely controlling the programming strength and thus manipulating its temperature coefficient,we propose a new setting method for the reference cells that programs each of reference cells to a charge state with a temperature coefficient closely tracking tail data cells,thereby solving the current coefficient mismatch and improving the read window.

QTL analysis reveals reduction of fruit water loss by NAC042 through regulation of cuticular wax synthesis in citrus fruit

Postharvest water loss is a critical factor that determines the quality and shelf life of fresh fruit.Cuticular wax constitutes a key barrier to reduce fruit water loss.Our previous study has shown that HJ(Citrus reticulata)has a significantly higher postharvest water loss rate than ZK(Poncirus trifoliata).Here,we investigated the fruit water loss rate of the HJ×ZK F1pseudo-testcross population in 2016 and 2019.QTL mapping for fruit water loss rate was performed by high-density genetic map and bulk segregant analysis,and QTL9 was identified to be associated with fruit water loss.The expression of NAC042 from QTL9 in ZK was 170-fold that in HJ.Heterologous expression in Arabidopsis showed that NAC042could reduce the water loss of leaves by increasing the cuticular wax content(especially alkanes).Further expression analysis revealed that NAC042 could enhance the expression of many wax-related genes in Arabidopsis leaves,including AtKCS1,AtKCS2,AtKCS9,AtKCS20,At CER1 and At CER3.Therefore,NAC042 might be involved in fruit cuticular wax synthesis to reduce fruit water loss.The findings provide new insights into the regulation of cuticular wax and fruit water loss as well as valuable information for breeding of citrus with better storability.

Spatiotemporal control of femtosecond laser filament-triggered discharge and its application in diagnosing gas flow fields

Precise control of the discharge in space and time is of great significance for better applications of discharge plasma.Here,we used a femtosecond laser filament to trigger and guide a highvoltage DC pulse discharge to achieve spatiotemporal control of the discharge plasma.In space,the discharge plasma is distributed strictly along the channel generated by the femtosecond laser filament.The breakdown voltage threshold is reduced,and the discharge length is extended.In time,the electrical parameters such as the electrode voltage and the electrode gap affect discharge delay time and jitter.By optimizing the parameters,we can achieve sub-nanosecond jitter of the discharge.Based on the spatiotemporal control of the discharge,we applied filamenttriggered discharge for one-dimensional composition measurements of the gas flow field.Besides,the technique shows great potential in studying the spatiotemporal evolution of discharge plasma.

THE CONVERGENCE OF NONHOMOGENEOUS MARKOV CHAINS IN GENERAL STATE SPACES BY THE COUPLING METHOD

We investigate the convergence of nonhomogeneous Markov chains in general state space by using the f norm and the coupling method,and thus,a sufficient condition for the convergence of nonhomogeneous Markov chains in general state space is obtained.

杂交小麦制种技术及除草剂在杂交制种提纯中的应用进展

杂交小麦技术可以提高小麦稳产性和丰产性,是保障粮食安全的重要策略.目前,杂交小麦制种成本过高,限制了杂交小麦大规模商业化推广.杂交小麦制种成本取决于单位面积杂交小麦产量、纯度以及单位面积播种量.在国内现有播种模式下,杂交小麦很难实现单位面积播种量的降低.提高单位面积制种产量和纯度,对降低杂交小麦制种成本就变得尤为重要.其中,通过喷施除草剂提高制种纯度,可以作为降低制种成本的一个有效手段.无融合生殖提供了杂交小麦制种的新维度,这种技术完全不用种植父本植株,将杂交制种转变成自交制种,可以进一步提高制种产量和纯度,降低制种成本.本文总结了近年来杂交小麦制种技术及除草剂在小麦制种纯度提升上的进展,并对未来创新技术方案进行了展望,以期加速杂交小麦的商业化推广.

CTAB Assisted Synthesis of CuS Microcrystals:Synthesis,Mechanism,and Electrical Properties

CuS microcrystals were successfully prepared through a mild solvothermal reaction in ethylene glycol （EG） with the assistance of cationic surfactant cetyltrimethylammonium bromide （CTAB）. An interesting morphology evolution from flower-like microspheres to hollow microspheres, and finally to smooth nanoflakes was observed when increasing the amount of CTAB. The products were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, and UV-vis spectroscopy. It was found that the amount of CTAB played an important role in determining the morphology of the CuS microcrystals. Electrical measurement reveals that the as-prepared CuS microspheres were of high conductivity, which might favor their device applications. It is expected that CuS microcrystals with controlled morphologies and structures will have important applications in solar cells. This simple but effective method could also be extended to the controlled growth of other inorganic microcrystals.