期刊文献+
共找到3篇文章
< 1 >
每页显示 20 50 100
大双直后超早熟玉米高产栽培模式的研究
1
作者 谭福忠 《玉米科学》 CAS CSCD 1998年第S1期71-72,共2页
大双直是一种与相适应品种结合进行的栽培方法,要求品种耐密植、抗倒伏、抗逆性强和产量高。克单8在黑龙江省第四积温区在密度是111100株/hm^2和施肥量是600kg/hm^2(尿素和磷酸二铵的商品用量比是1.2∶1)时,产量可达到11980kg/hm^2。... 大双直是一种与相适应品种结合进行的栽培方法,要求品种耐密植、抗倒伏、抗逆性强和产量高。克单8在黑龙江省第四积温区在密度是111100株/hm^2和施肥量是600kg/hm^2(尿素和磷酸二铵的商品用量比是1.2∶1)时,产量可达到11980kg/hm^2。这种方法在我国年有效积温低于2200℃的地区大有发展前景。 展开更多
关键词 玉米 超早熟 栽培模式 大双直
下载PDF
松嫩平原黑土带玉米高产栽培模式
2
作者 王俊河 《黑龙江农业科学》 2003年第1期38-40,共3页
关键词 大双覆栽培模式 大双直模式 大垄覆膜立体通透模式 松嫩平原黑土带 玉米 高产栽培模式
下载PDF
A Highly Linear Filter and VGA with DC-Offset Correction for GSM/WCDMA Receivers
3
作者 周竹瑾 李志升 +2 位作者 李宁 李巍 任俊彦 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第3期372-376,共5页
This paper describes a complete baseband chain for both GSM and WCDMA receivers with a SMIC 0.35μm mixed signal process. The chain consists of a dual-mode,highly linear, fourth order Chebyshev active RC filter and th... This paper describes a complete baseband chain for both GSM and WCDMA receivers with a SMIC 0.35μm mixed signal process. The chain consists of a dual-mode,highly linear, fourth order Chebyshev active RC filter and three VGA stages. The filter is designed to meet the bandwidth specifications of the GSM and WCDMA standards and share the maximum number of components between the two modes to reduce manufacturing cost. The design is free of DC-offset and has an inter-stage high-pass filter, and operational amplifiers with adjustable GBW are used to minimize GSM-mode power consumption. The measured noise figures are 27. 3 and 42dBm in WCDMA and GSM modes,respectively, at the maximum gain. The IIP3 is 40dBm at unit gain in the WCDMA mode,and the circuit consumes 47.0mW. The IIP3 is 28dBm in the GSM mode,and the circuit consumes 31.8mW. The supply voltage is 3.3V. 展开更多
关键词 active RC filter VGA Tow-Thomas DC-offset correction DUAL-MODE
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部