Wyniki wyszukiwania - Biblioteka Nauki

1

Low Offset, High PSRR, CMOS Bandgap Voltage Reference

100%

Zhao Y. , Lai X.

Przegląd Elektrotechniczny

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2013

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tom R. 89, nr 1b

174--177

EN

A CMOS Bandgap Voltage Reference (BVR) with the characteristics of low offset and high power-supply rejection ratio (PSRR) is presented. In order to reduce the effect of offset of operation amplifier (OPA), the voltage difference of base-emitter junctions of substrate bipolar transistors is maximized; meanwhile the factor of offset voltage could be minimized. The feedback loop constructed by proportional to absolute temperature (PTAT) current source and an OPA is employed to improve the PSRR. The circuit was designed and simulated in a standard 0.35-μm CMOS process, with a power supply of 3 volt. The relative accuracy is increased by 5 times compared with conventional circuit. PSRR of the circuit is ～108dB at low-frequency. Furthermore, temperature coefficient (TC) of 17ppm/℃ over a wide temperature range of －40～115℃.The whole circuit including the OPA draws only 22 μA from supply voltage. Silicon area is 0.037mm2.

PL

Opisano pasmowy wzorzec napięcia w technologii CMOS charakteryzujący się małym pełzaniem zera i dużym współczynnikiem usuwania składowej zasilającej. Układ zaprojektowano w technologii 0.35μm z napięciem zasilania 3V.

2

Advantages of small-seeded species in forests: win-win for temporal and spatial dispersal among seeds in Rhododendron

80%

Wang H. , Lai X. , Zhang Y. , Chen H.

Polish Journal of Ecology

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2019

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tom 67

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nr 1

EN

There is little consistent evidence for evolutionary associations from seed production to seedling fitness. In this study, 20 species of Rhododendron genus were selected from subtropical forests of southwest China; the life-history functional traits such as the seed size, seed number per twig, germination traits, dispersal and seedling survival were investigated, the ecological relationships among them were tested and the advantages of small-seeded species were discussed. The results show that the quantitative parameters of germination, such as the germination rate, potential, and index are positively correlated with seed number produced per stem, while temporal parameters, such as germination peak timing and duration are positively correlated with seed size. The two results indicate that different Rhododendron species with different seed sizes and relative seed number can deal with varying environments according to spatial dispersal or time dispersal, respectively, and the advantages of smaller seeds in the aspect of sprouting vigour, dispersal ability and seedling survival may lay the foundation for the establishment of small-seeded plants in the forest.

3

Effects of the Three Gorges Project on the environment of Poyang Lake

80%

Li D. , Lai X. , Dong Z. , Luo X.

Polish Journal of Environmental Studies

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2016

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tom 25

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nr 6

EN

Impounding by the Three Gorges Project (TGP) changed the hydrological process and affected the ecosystem in the middle and lower reaches of the Yangtze River. Poyang Lake is closely linked with the Yangtze River. This paper presents a coupled numerical model designed for simulating the tempo-spatial variation of water quantity and quality in the lake’s water system that features complex river-lake interactions. According to the calculated results of a typical year (2000) under two scenario schemes, we evaluated TGP’s effects on the ecological environment of the lake. The results show that due to TGP impoundment, the hydraulic gradient at the lake outlet has increased and that the outflow fluctuates dynamically and regularly with the increase and decrease of the TGP released discharge. The lake water level falls in advance and the average reduction magnitude of the water level decreases progressively from north to south, showing a spatially uneven effect, which is 0.95 m, 0.70 m, 0.74 m, 0.35 m, and 0.80 m at Xingzi, Tangyin, Duchang, Kangshan, and Wucheng stations, respectively. The ammonia nitrogen output from the lake to the Yangtze River increases and the total ammonia nitrogen amount within the lake region decreases. The average ammonia nitrogen concentration within the lake region tends to increase slightly and the influence magnitude on the concentration is reduced from north to south. The wetland vegetation area fluctuates dynamically with the decline of the water level, and the increase of the wetland vegetation area ranges from 0.64 to 215.48 km2. As a result of the falling water levels, the bottomlands in the lake region are exposed relatively earlier and the continuous exposure days increase, which intensifies the problem that migrant birds do not have enough food. Meanwhile the number of days when the bottomland and wetland are submerged decrease, which will further accelerate the degradation succession of wetland vegetation.

4

Przygotowanie ekstraktów polisacharydowych pyłku chryzantemy i ich wpływ na komórki in vitro raka jelita grubego

61%

Fang Z. , Luo R. , Jiang M. , Jiang G. , Fu M. , Chen S. , Lai X.

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tom T. 97, nr 10

1733--1736

PL

Polisacharydy zawarte w pyłku chryzantem ekstrahowano wodą i wytrącano przy użyciu alkoholu. Cukier o charakterze obojętnym i 2 cukry o charakterze kwasowym rozdzielono, stosując chromatografię jonowymienną. Skład monosacharydów oznaczono metodą wysokosprawnej chromatografii cieczowej. Działanie przeciwnowotworowe polisacharydów oceniano, badając ich wpływ na proliferację komórek nowotworowych. Hamowanie proliferacji HCT116 nie było znaczące, gdy stężenie wynosiło 5 mg/mL (p > 0,05), jednak działanie to w stosunku do komórek nowotworowych HCT116 i HT-29 było znaczące przy tym samym stężeniu (p < 0,05). Nieprzetworzone wyciągi polisacharydowe miały większy wpływ na proliferację komórek in vitro raka jelita grubego niż poszczególne polisacharydy.

EN

Polysaccharides were extd. from Dendranthema indicum var. Asteraceae bee pollens with H2O (yield 7.9%), pptd. with EtOH and sepd. by ion-exchange chromatog. into a neutral sugar and 2 acidic ones. The monosaccharide compn. was detd. by high performance liq. chromatog. They contained rhamnose, galacturonic acid, glucose, galactose and arabinose. The anticancer activity of the polysaccharides was evaluated by studying their effect on proliferation of HCT116 and HT-29 cancer cells. The inhibitory effect of individual sugars on the proliferation of HCT116 was not significant when their concns. were 5 mg/mL, but the total polysaccharides showed a significant effect on proliferation of HCT116 and HT-29 tumor cells at the same concn

5

Cloning of Hsp21 gene and its expression in Chinese shrimp Fenneropenaeus chinensis in response to WSSV challenge

61%

Gao H. , Lai X. , Kong J. , Wang W. , Meng X. , Yan B. , Cai S.

Journal of Applied Genetics

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2014

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tom 55

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nr 2

6

Associations between polymorphisms in the NICD domain of bovine NOTCH1 gene and growth traits in Chinese Qinchuan cattle

51%

Liu M. , Zhang C. , Lai X. , Xue J. , Lan X. , Lei C. , Jia Y. , Chen H.

Journal of Applied Genetics

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2017

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tom 58

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nr 2