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101.
第三代短波通信系统的自动链路建立协议(3G-ALE)具有更高的数据速率和更强的噪声适应能力,研究3G-ALE信号的检测和参数估计技术对电子侦察和干扰具有重要意义。在推导了多径和衰落信道对信号自相关的影响后,提出一种载波检测与估计方法,即信号经过相关运算后,运用现代功率谱估计的方法,实现对3G-ALE信号的检测与载波估计,并进行性能仿真。仿真结果证明了多径衰落条件下所提出的检测方法的有效性。  相似文献   
102.
中水回用处理技术   总被引:1,自引:0,他引:1  
污水处理厂出水由进水泵进入中水回用系统,进入后首先通过PAM和PAC加药泵加入药剂,混合后进入机械过滤器,经过滤后再进入活性炭过滤器,在罐中处理后流出,两个过滤器主要去除的是SS、石油类、氨氮和少量COD。过滤后的污水经过二氧化氯发生器进行混合消毒后排出,处理后的中水主要是用于绿化用水、消防补水、冲厕用水和循环水补水。  相似文献   
103.
《Ceramics International》2023,49(15):25135-25143
In this paper, 304 stainless steel-based ZnO (304SS-based ZnO) seed layer was prepared by using sol-gel method or electrochemical deposition. Superhydrophobic nano-ZnO (CSS–ZnO) surface were prepared on its surface by hydrothermal method. The results show that different structural morphologies of 304SS-based ZnO surface were prepared by varying different seed layer preparation methods. In the static icing test, compared with hydrophilic nano-ZnO (SS–ZnO) surface, hydrophobic nano-ZnO (QS-ZnO) surface and 304SS surface at −5 °C, −10 °C and −15 °C. The icing time of CSS-ZnO surface was prolonged by about 2.7 h at −5 °C, delayed by about 40 min at −10 °C and delayed by about 9 min at −15 °C. The CSS-ZnO surface is the most effective surface in static anti-icing. It is because that there has a residual air layer at the solid-liquid interface and the coating can still effectively retard ice formation in a partially wetted state. In the dynamic icing test, compared with QS-ZnO surface, SS-ZnO surface and 304SS surface at −16 °C, SS-ZnO surface and QS-ZnO surface have no anti-icing effect, and CSS-ZnO surface has a significant anti-icing effect. The mechanism for inhibiting condensation of water droplets by superhydrophobic surfaces was illustrated, which can be identified that the contact angle of the ice embryo will increase with the increase of the water contact angle. This work provides a practical application for promoting anti-icing ability of 304SS surfaces in industry.  相似文献   
104.
简要介绍了长网双缸纸机运行中降低吨纸耗水量、减少排放水中固体物质含量的一些措施,保护了环境,降低了生产成本.  相似文献   
105.
副溶血性弧菌是水产品中主要的致病菌之一,既可造成养殖水产品的疾病与死亡,也可引起人类的胃肠炎等疾病,不仅具有潜在的食品安全隐患,也对消费者健康造成潜在危害。该文主要阐述了副溶血性弧菌的毒力因子耐热直接溶血素(thermostable direct hemolysin, TDH)以及分泌系统T3SS1、T3SS2在菌株体内的作用机理,并对副溶血性弧菌产生耐药性的5种机制——产生生物被膜、质粒介导耐药、产生灭活酶或钝化酶类、外排泵主动排出抗菌药物、药物靶点发生改变进行了综述。  相似文献   
106.
A novel process for the one-step conversion of primary and secondary alcohols into their O-alkyl-S-methyl dithiocarbonates was developed using Amberlite IRA 400 (basic resin) in presence of carbon disulfide. O-Alkyl-S-methyl dithiocarbonates of various alcohols were isolated in very good to excellent yields. This protocol is mild and efficient compared to other existing methods.  相似文献   
107.
新一代TMCP技术就是以超快速冷却技术为核心的NG-TMCP技术。采用该技术,可大批量生产低成本的HRB400热轧带肋钢筋,其主要规格为16、18、20和25mm,且各项性能指标符合国标GB1499.2的规定。采用该技术,可降低钢筋中的钒含量,使吨钢减少成本40元。  相似文献   
108.
In this study, microchannels with widths of 60, 100, 150, 200, and 250?µm were fabricated on the surface of Monel 400 alloy, and the effect of the rolling direction on the surface finish and etching depth was investigated. The obtained results revealed that the quality of the microchannel surface finish was better along the rolling direction than across the rolling direction, owing to the grain boundary orientations along the (001) plane. In addition, the etching depth increased along the rolling direction due to the presence of residual stress and plastic strain, which ultimately improved the microchannel quality.  相似文献   
109.
2000年问题是IT行业要迫切解决的问题。分析了AS/400的2000年问题,并且给出了一个可行的AS/400 2000年问题实施方案。  相似文献   
110.
The purpose of this study was to understand the kinetics of emptying of micronised salbutamol sulphate (SS) and lactohale 300 (LH300) under varying air flow rates (30–180 L min−1) from three dry powder inhaler devices, Rotahaler® (RH), Monodose Inhaler® (MI) and Handihaler® (HH). Aerosol concentration vs. time profiles, determined through real-time laser diffraction particle sizing, demonstrated that the majority of the powder from RH was emitted within one second while a more prolonged aerosolisation was observed from MI and HH. Peak aerosol concentrations were achieved more rapidly from RH compared to MI for both SS and LH300. Calculated cumulative emitted mass (CCEM) vs. time profiles were obtained from the aerosol concentration vs. time profiles and the emitted mass and the rate of CCEM (kCCEM), estimated from a modelling approach, increased with increasing air flow rates. The kCCEMvs. air flow rate profiles of SS and LH300 were significantly different at high air flow rates. The kCCEM was highest from RH and lowest from MI. Differences in kCCEM between the devices were related to capsule aperture size while the differences between the materials were due to the powder bed structure. This approach provided an understanding of the rate at which powder mass emptied from dry powder inhaler devices and was proposed to be a powerful development tool for the future powder inhalers.  相似文献   
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