MAX7219在带清零与置数功能的增量式光电码盘中的应用

介绍了用高性能八位串行接口LED驱动芯片MAX7219,实现带置数与清零功能的增量式光电码盘静态显示。机上系统采用AT89C51实现码盘清零与置数功能,软件设计实现分、秒的六十进制压缩BCD码加、减运算;机下系统采用AT89C2051控制MAX7219串行驱动7位共阴极数码管,显示从串行接口接收到的码盘位置检测角度值。     

基于 FPGA 的多通道温度采编装置设计

针对飞行试验中对设备温度测量的需求,设计了一种适用于飞行测试的高精度多通道温度采编装置。设计以FPGA构建信号采集处理系统,采用AD8227和AD590来实现信号的调理和温度冷端补偿,通过标准RS422协议实现16路温度信号传输,并采取线性拟合的方式对输出进行非线性校正,提高了系统准确率和稳定性。测试结果表明,测温电路全量程内最大测量误差为±0.083%F.S.。经过测试验证,该方案传输过程无丢帧零误码,系统运行高效、可靠。     

A novel coumarin‐based fluorescent probe for selective detection of cysteine over homocysteine

A coumarin‐based fluorescent probe containing both acrylate moiety and an allyl substituent was developed for distinguishing cysteine from homocysteine. The maximum absorption wavelength of the probe showed a bathochromic shift upon addition of cysteine and the colour changed from colourless to yellow. The maximum fluorescence emission at 462 nm of the probe was dramatically enhanced upon addition of cysteine in aqueous solution. In HEPES buffer (pH = 7.4, EtOH/H₂O = 9:1, v/v), both of the fluorescence emission bands of the probe at ca. 390 and 462 nm were intensely enhanced upon the addition of cysteine, while other amino acids, namely, homocysteine, asparaginic acid, methionine, glycine, phenylalaninase, valine, tryptophan, serine, glutamic acid and glutathione, did not cause a remarkable change. The probe can be used for selectively colorimetric and ratiometric fluorescent detection of cysteine over homocysteine and other common amino acids in both organic media and aqueous solution. The concentration of cysteine can be estimated by titration of the probe in aqueous solution, and the detection limit of the probe towards cysteine was 2 μmol/L.     

基于云原生服务网格的AI模型部署方案

人工智能模型训练完成后并不适合直接运行在互联网生产环境,需要对其进行一定的封装和部署.探讨基于容器和云原生服务网格对AI模型进行自动封装和部署,以微服务形式对外提供Restful API,能够提高模型的兼容性和部署灵活性.封装过程采用适用多框架的通用AI模型代码打包方法,解决AI模型运行环境配置问题;通过部署在云原生平...     

Mebendazole-Induced Blood-Testis Barrier Injury in Mice Testes by Disrupting Microtubules in Addition to Triggering Programmed Cell Death

Mebendazole (MBZ) is a synthetic benzimidazole known for its antiparasitic properties. In recent years, growing evidence showed that MBZ was also used as an anti-tumor agent. However, whether (and to what extent) this drug treatment affected the male reproductive system was not well-understood. In this study, male C57BL/6 mice were injected with 40 mg/kg/day of MBZ. The treatment was for 3 and 7 days. Our results showed that the injected mice exhibited an abnormal spermatogenic phase with a significant decrease in sperm. We further detected microtubule disruption and transient functional destruction of the blood–testes barrier (BTB) in the MBZ-injected mice testes (BTB). Our data confirmed that MBZ suppressed the expression of the BTB junction-associated proteins and disrupted the Sertoli cells’ function in vivo. Moreover, MBZ-treated mice demonstrated an aberrant caspase-3 signalling pathway, which resulted in the apoptosis of the germ cells. Here, we present our data, indicating that MBZ impairs BTB by reducing the expression of the microtubules’ and BTB junction-associated proteins. The last leads to activating the caspase-3 pathway, which triggers extensive germ cell apoptosis.     

金瓜气调贮藏实验研究

利用气调贮藏实验系统对金瓜保鲜进行了初步研究。结果表明,在温度7～8℃、O2平均浓度约3%、CO2浓度自然上升至8%～10%范围内,其保鲜效果不如同温度下的自然冷藏保鲜效果。与低温低湿比较,在本实验范围内,低O2高CO2对病原菌的抑制作用不明显。     

纸质文献表面自由能测试方法的探索

本研究探讨了6种纸质文献的表面自由能（简称表面能）测试方法,以Zisman法的测量值为基准,比较了Neumann法、ZDY法、HM法、OWRK法、OCG法,选取更简便且理论数据与实际测量值相符合的测量方法。结果表明,Zisman法所得纸张表面能为26.24 mJ/m²,纸张施胶后表面能转低,难润湿;Neumann法的测量结果较好,且能最大程度简化表面能的测试步骤,在大规模脱酸处理中能提高古籍的修复效率,并能减少对纸张的损害。ZDY法的实际测量值和理论数据差距较大,不适合用于测量纸张表面能。HM法选择二碘甲烷和丙三醇作为检测液体时,所得偏差较小。OWRK法、OCG法需选择适当的检测液减小标准偏差,若检测液选择不当,会得出与实际不符的结论。     

石油烃污染土壤微生物修复技术研究现状及进展

土壤石油烃污染已引起广泛关注,石油烃具有高毒性和持久性,对生态环境和人体健康会产生严重危害。本文综述了石油烃污染土壤修复技术的国内外研究进展,系统论述了微生物技术在石油烃污染土壤修复中的研究现状,重点探讨了微生物联合修复技术的过程机制和应用前景,包括植物-微生物联合修复、电动-微生物联合修复、表面活性剂强化微生物修复、化学氧化-微生物联合修复及动物-微生物联合修复等,并对未来石油烃污染土壤微生物修复技术的研究发展方向提出了展望。     

麦羟基硅钠石的可控合成及其阳离子交换性能研究

目前,开发绿色高效的重金属吸附材料受到人们的广泛关注。以硅藻土为原料,经水热法选择性地制备了2类硅酸盐材料即麦羟基硅钠石和方沸石。吸附测试结果表明,麦羟基硅钠石层间的钠离子能够与锂离子、镁离子、锌离子、钴离子、镍离子、铜离子等进行阳离子交换且能保持层状母体框架的稳定性。以钴离子、镍离子为例深入研究其吸附动力学和吸附机制发现,钴离子和镍离子的嵌入分别将麦羟基硅钠石的层间距由本征的1.56 nm减小到0.24、0.23 nm;室温下,对钴离子、镍离子的最大吸附量分别可达45、39 mg/g,均符合Langmuir单层吸附模型;钠离子的置换量大约是吸附的钴离子、镍离子量的两倍,证实层间离子交换主导吸附化学过程。因此,麦羟基硅钠石材料在多金属硅酸盐功能材料的合成以及环境吸附净化领域具有较大的应用潜力。