Effect of corona discharge plasma jet treatment on decontamination and sprouting of rapeseed (Brassica napus L.) seeds

Sprout-related outbreaks of foodborne illnesses are increasingly becoming a food safety concern. Different pathogenic microorganisms that originate from sprout seeds are known to play a crucial role in the pathogenesis of such outbreaks. Therefore, in order to decontaminate and also to enhance the germination of seeds, the applications of non-thermal plasma based techniques are increasingly being investigated in the field of agricultural science as an alternative to conventional pre-germination treatments. This work was aimed to evaluate the effectiveness of corona discharge plasma jet (CDPJ) for microbial decontamination of rapeseed seeds, and also studied the plasma treatment effect on the seed germination and physicochemical properties of sprouts (grown from the plasma-treated seeds). Aerobic bacteria, molds and yeast, Bacillus cereus, Escherichia coli, Salmonella spp. were detected as contaminants in the seeds. All the detected microorganisms were reduced in the range of 1.2–2.2 log CFU/g upon the CDPJ treatment for 3 min. The inactivation patterns are better explained using pseudo-first-order kinetics. The plasma treatment of seeds up to 2 min showed positive effects on their germination rate and seedling growth. Physicochemical and sensory characteristics of rape sprouts were unaffected due to the CDPJ treatment of their respective seeds. Therefore, the CDPJ treatment of rapeseed seeds has not only reduced the seed microbial load, but also contributed to the enhancement of their germination rate and seedling growth, without adversely affecting the physicochemical and sensory characteristics of their corresponding sprouts.     

高温合金激光表面熔掺Y_2O_3质点的研究

本文通过激光辐照的方法,研究了在高温合金试样表面掺杂Y_2O_3质点的可能性、均匀程度与激光辐照参数的关系。结果表明,当预涂粉末数量为0.035g/cm~2和0.059g/cm~2时,选择功率密度为1.76×10~4w/cm~2,扫描速度为0.36m/min时,可获得Y_2O_3质点在熔掺区中宏观上的均匀分布,其氧化钇的含量达1.2～2.0Wt％。     

低剂量CO_2激光对茄子种子活力影响的研究

低剂量激光照射种子对其发芽率、发芽势、酶活性均有一定的刺激效应。郝丽珍等曾在青椒上作过研究。本文在茄子上也得到了类似的结果,进而为蔬菜种子播前处理提供了依据。 1 材料和方法 茄子品种为七叶X紫茄,含水量为8.33％,试验均选用饱满的大小均一的中等种子。将种子置于自制的种盘内照射,CO_2激光扩束后功率为4.05W,光斑直径为2.5cm,照射距离为     

长脉冲激光沉积原位生成YBaCuO超导膜

用长脉冲激光(脉冲宽度150μs,波长1.06μm)辐照高温烧结的YBa_2Cu_3O_(7-x)靶,在6Pa的氧气压强下,巳在(100)YSZ单晶衬底上原位生成YBa_2Cu_(?)O_(7-x)超导膜。衬底置于750℃的加热器上,衬底与靶之间的距离5cm,用该法制得的薄膜光亮坚实,正常态呈金属性,零电阻温度为84.7K。用XRD和SEM对薄膜进行了分析研究。     

准连续Ti~(3+):Al_2O_3可调谐激光的研究

本文给出了Ti~(3+):Al_2O_3的准连续可调谐激光的实验结果。采用Nd:YAG内腔倍频532nm的准连续输出作为泵浦源,得到Ti~(3+):Al_2O_3的连续可调谐输出。波长覆盖范围为685nm到821nm。最大输出功率为293mW,斜率效率为20％,在805nm处的窄谱输出功率达240mW,总体转换效举为26％。     

同时测量氢和氧CARS谱的新方法

提出一种仅需一台染料激光器即可同时测量火焰中氢和氧的CARS谱的新方法.取带宽为120cm~(-1).中心波长位于580.4nm的Stokes光束与532nm的泵浦光束相配合.同时测量氢扩散火焰中的氢和氧的CARS谱.用氢的S(6)和S(5)的积分强度比确定火焰中的温度并与氮的Q支CARS谱测量的温度和经过热损耗修正的热电偶测得的温度取得了相当好的一致结果.一次测出氢和氧的CARS谱.避免多次测量中参数的难以重复性.提高了以温度为参数来确定浓度的准确性.     

I/O System Four电缆结构及故障排除

电缆是现代地震勘探仪器系统的主要辅助设备之一，担任传输数据和命令的任务。本文介绍了I／O System Four电缆结构，并对其常见故障进行了详细分析。     

A Versatile Pt‐Based Core–Shell Nanoplatform as a Nanofactory for Enhanced Tumor Therapy

Hypoxia, one of the representative characteristics in solid tumors, not only reduces the effectiveness of multiple treatments, but also relates to the tumor invasion and metastasis. Here, a hybrid core–shell nanoplatform to produce adequate oxygen, supporting for more effective tumor treatment, is developed. Composed of polydopamine cores, platinum nanoparticle interlayers, and zirconium‐porphyrin (PCN) shells, the hybrid core–shell nanoplatform works like a nanofactory, providing necessary products at different time and space. Platinum nanoparticle interlayers can catalyze the endogenous H₂O₂ to O₂, which plays a dual rule in the enhanced tumor treatment. In the presence of light irradiation, O₂ can be converted into the lethal reactive oxygen species by the PCN shell. In the absence of light irradiation, O₂ ameliorates the hypoxic microenvironment, thereby reduces the invasion and metastasis of the tumor. Through a synergism of enhanced treatment and reduced metastasis, tumors could be treated more vigorously.