Caffeine, a significant naturally occurring alkaloid in beverages like tea and coffee, can be degraded by bacteria. Prolonged caffeine consumption can stimulate adrenal glands, cause irregular muscle activity, cardiac arrhythmias, and withdrawal symptoms such as headaches and fatigue. Beyond its health-related concerns, the environmental impact of caffeine degradation is noteworthy. Effluents from coffee industries contain high caffeine concentrations, and the discharge of such effluents into lakes poses a risk to the portability of drinking water. This study isolated a novel bacterium from agricultural soil, identified as Bacillus sp. KS38 through 16 S rRNA gene sequencing, which can metabolize caffeine as the sole carbon and nitrogen source. The bacterium exhibited Gram-positive characteristics. Response surface methodology (RSM) optimized bacterial growth conditions. The relevant parameter for the degradation of caffeine was obtained by first screening the parameters using the Plackett-Burman design. Using central composite design (CCD) and RSM, the important parameters were determined to achieve the ideal degradation conditions. The identified the ideal degradation conditions: 0.66 g/L caffeine, 0.85 g/L glucose, pH 6.83, and 20.5 degrees C. RSM predicted a bacterial growth of 0.591, which was confirmed experimentally. This bacterium has potential applications in wastewater treatment and caffeine bioremediation.
Global warming increases the frequency and intensity of climate extremes, but the changes in climate extremes over the Antarctic Ice Sheet (AIS) during different periods are unknown. Changes in surface temperature extreme indices (TN10p, TX10p, TN90p, TX90p, CSDI, WSDI, TNn, TNx, TXn, TXx and DTR) are assessed during 2021-2050 and 2071-2100 under SSP1-2.6, SSP2-4.5, SSP3-7.0 and SSP5-8.5, based on the multi-model ensemble mean (MMEM) from the Coupled Model Intercomparison Project Phase 6 (CMIP6). The extreme indices, excluding TXn and DTR, illustrate the opposite trend in the two periods in SSP1-2.6 over the AIS. Generally, the changes in extreme indices reflect the continued warming over AIS in the future, and the warming is projected to intensify in SSP3-7.0 and SSP5-8.5. The variations in the extreme indices exhibit regional differences. The Antarctic Peninsula displays rapid changes in TNn, TXn and DTR. In SSP5-8.5, the magnitudes of all climate index tendencies are greater during 2071-2100 than 2021-2050. The variations in TX10p, TX90p, TN10p, TN90p, WSDI and CSDI are faster in the Antarctic inland than in the other regions over the AIS. However, the decrease in the DTR is concentrated along the AIS coast and extends to the interior region, whereas the increasing trend occurs in the Antarctic inland. In West AIS, TX90p and TN90p rapidly increase during 2021-2050, whereas the rapid changing signals disappear in this region in 2071-2100. The dramatic changes in TNn, TXn and DTR occur at the Ross Ice Shelf during 2071-2100, indicating an increased risk of collapse. For TNx and TXx, the degree of warming in the later part of the 21st century is divided by the transantarctic mountains, and greater changes appear on the eastern side. Generally, Antarctic amplification of TNn, TXn and DTR is observed except under SSP1-2.6. In addition, TNx and TXx amplifications occur in SSP3-7.0 and SSP5-8.5.
为了提高冻土试验系统的控温精度、实现分凝冰发育过程的实时监测,基于固态制冷技术和线阵CCD(Charge Coupled Device)扫描成像技术,研发一种新型冻土可视化试验系统。该系统的核心部件包括固态控温模块和CCD可视化模块。在固态控温模块中,引入人工神经网络对控温算法的控制参数进行优化选取,使得试验系统对控温对象的温度状态具备自适应调节能力。而在CCD可视化模块中,使用CCD感光元件构建了操作简便、成像精度高的线阵扫描结构,其最高分辨率可达4 800 dpi×4 800 dpi。性能测试结果显示系统的恒温控制精度为±0.002℃。在变温幅度为0.05℃的控温过程中,其温度过冲只有0.009℃;当变温幅度增加至0.5℃时,其温度过冲仅为0.089℃。而在线性降温过程中(降温速率-1.2℃/h),其控温误差未超过±0.01℃。在此基础上,开展正弦温度波动下的应用试验。从试验结果上看,该系统运行稳定、控温精度高,可视化模块可观测到0.5mm宽度的分凝冰发育过程。并且所得数据表明土体过冷过程和冻融历史对温度场、分凝冰发育状态存在显著影响。因此,当前冻胀试验中为了消除过冷影响而采取的预...
TDI-CCD相机可以通过多级CCD积分,获得相对较高的信噪比,从1992年开始逐步广泛应用于航空和航天领域中的高分辨率成像任务中。目前TDI-CCD相机已成为高分辨率成像探测的重要手段。根据月球环绕探测任务中TDI-CCD相机的工作环境特点,定量分析了相机的姿态误差、速高比失配等因素对成像质量的影响,并对其中的主要影响因素——速高比失配,提出了适合于月球环绕探测任务特点的补偿途径。
"中国首次月球探测工程全月球影像图"是我国第一幅覆盖月球的遥感影像图,将成为嫦娥工程后期探测和月球科学研究的重要基础图件.详细介绍了嫦娥一号CCD图像数据的获取、数据特点和数据质量,描述了图像数据的处理方法和流程,按制图规范对图像数据进行了镶嵌拼接和处理,制作了覆盖全月球的1:250万比例尺影像图,并进行了影像图的定位精度分析.数据处理和制图结果表明,嫦娥一号CCD数据及其定位精度能够满足1:250万比例尺的制图要求,制作的"中国首次月球探测工程全月球影像图",其相对定位精度优于240m,平面定位精度约为100m~1.5km,定位精度略好于2005联合控制网(ULCN2005)和克莱门汀基础地图(2.0版);对所有像元进行了逐一光度校正,大大改善了全球图像的一致性,是目前覆盖最全、图像质量最好、定位精度最高的全月球影像图.
SIFT算法具有较强的匹配能力,能够处理两幅影像之间在发生平移、尺度、旋转、光照、视角等变化的情况下的匹配问题。利用SIFT算法进行影像匹配,根据匹配点计算两幅影像之间的仿射参数,将左影像上的格网映射到右影像作为初始点,然后使用相关系数测度在右影像上初始点邻域范围搜索匹配点。实验结果表明,该方法能够得到很好的匹配效果。
"嫦娥"卫星三线阵CCD立体相机是实现月表地形观测的重要荷载,其以前、正、后视3种视角对月表进行连续扫描,获得南、北纬70°范围内3种不同倾角的二维推扫影像。在无月面控制点、卫星位置和姿态数据的条件下,基于数字摄影测量理论提出一种建立月表三维模型的方法:通过影像匹配获得前、正、后视二维推扫影像中的立体像对的像点坐标,在此基础上结合用准控制点后方交会解得的嫦娥卫星的空间位置和姿态数据,通过前方交会的方法解算出像元对应月面点的月球表面数字高程模型(DEM)径向高度数据,进而得到月表高程拟合模型、等高线分布图等,实现月表三维模型的建立。
研究了月球目标探测成像及自动跟踪系统。利用CCD图像传感器、图像处理技术以及图像跟踪算法可以取代对月球的手动跟踪,无需预知月球的运动轨道,在自动跟踪的同时记录月球影像,便于对月球表面数据的记录和处理,并能进行实时图像处理,利于对月球图像的分析,为月球探测跟踪做了一次有益的新方法尝试。
月球是目前世界各国进行深空探测的首选星球,月球探测卫星属于传输型卫星。本文利用三线阵CCD摄影测量理论对月球摄影测量处理进行了可行性分析,指出其关键技术并提出解决方案,最后通过模拟实验进行验证.研究结果表明:三线阵CCD摄影测量理论可以较好地解决我国月球探测中的某些难题,完全可以应用于月球摄影测量中。
本文对月球卫星摄影三线阵CCD影像的EFP(等效框幅相片)光束法空中三角测量作两种处理:一是与现行摄影测量常用的将平差转到切面坐标系进行,二是在摄影测量坐标系内,长航线自由网EFP光束法平差利用三线CCD推扫特点,在EFP平差中增加对前、后视影像的相机主距的附加改正项,用以补偿由于球面曲率产生的前、后视影像比例尺的差异,平差得到的是平面基准的地面坐标及外方位元素的平差值。前者计算,数学上严格,但长航线要适当分段为切面处理;后者计算数学上有近似性,可方便地用于估算卫星姿态变化率,或作地面模型的几何反演等实验研究。利用嫦娥一号获取的第一条航线,并给出相应的结果。