Ｖａｒｉａｔｉｏｎ Ｃｈａｒａｃｔｅｒｉｓｔｉｃｓ ａｎｄ Ｆｒａｃｔｉｏｎｓ ｏｆ Ｏｘｉｄｉｚａｂｌｅ Ｏｒｇａｎｉｃ Ｃａｒｂｏｎ

以9种沙生植被为研究对象,沙裸地为对照,采用野外调查与室内分析相结合的方法,分析不同沙生植被土壤易氧化有机碳(Coc)各组分的变化特征,并在此基础上提出土壤有机碳活性系数和敏感指数,探讨不同沙生植被对改善土壤质量的影响。结果表明:沙裸地种植植被后,Coc各组分和总有机碳(Ctoc)含量显著增加,但Coc各组分占Ctoc的比例无明显变化;与其他沙生植被相比,刺槐林(Robinia pseudoacacia)、花棒(Hedysarum scoparium)、臭柏(Sabina vulgaris)和樟子松(Pinus sylvestris var.mongolica)对改善土壤质量,提高土壤有机碳活性的作用更加显著。敏感指数表明Coc中第1部分(Cfrac1)和第2部分(Cfrac2)活性较强,其中Cfrac1对土壤质量变化更加敏感,可以作为衡量土壤质量状况的良好指标。相关性分析表明Cfrac1,Cfrac2,Cfrac3,Cfrac4,Coc与Ctoc之间极显著相关(P<0.01),与碱解氮和全氮成显著或极显著正相关(P<0.05或P<0.01),与全磷和速效磷之间的相关Ａｂｓｔｒａｃｔ：Ｔｈｅ　ｖａｒｉａｔｉｏｎ　ａｎｄ　ｆｒａｃｔｉｏｎｓ　ｏｆ　ｏｘｉｄｉｚａｂｌｅ　ｏｒｇａｎｉｃ　ｃａｒｂｏｎ（Ｃｏｃ）ｆｒｏｍ　ｎｉｎｅ　ｐｓａｍｍｏｐｈｙｔｅｓ　ｗｅｒｅ　ｓｔｕｄｉｅｄ　ｔｈｒｏｕｇｈ　ｆｉｅｌｄ　ｉｎｖｅｓｔｉｇａｔｉｏｎ　ａｎｄ　ｌａｂｏｒａｔｏｒｙ　ａｎａｌｙｓｉｓ．Ｓｏｉｌ　ｓｅｎｓｉｔｉｖｅ　ｉｎｄｅｘ　ａｎｄ　ｔｈｅ　ｉｎｆｌｕｅｎｃｅ　ｏｆ　ｄｉｆｆｅｒｅｎｔｖｅｇｅｔａｔｉｏｎｓ　ｏｎ　ｓｏｉｌ　ｑｕａｌｉｔｙ　ｉｍｐｒｏｖｅｍｅｎｔ　ｗｅｒｅ　ａｌｓｏ　ｄｉｓｃｕｓｓｅｄ．Ｒｅｓｕｌｔｓ　ｓｈｏｗｅｄ　ｔｈａｔ　ｔｈｅ　ｃｏｎｔｅｎｔｓ　ｏｆ　Ｃｏｃａｎｄｔｏｔａｌ　ｏｒｇａｎｉｃ　ｃａｒｂｏｎ（Ｃｔｏｃ）ｉｎｃｒｅａｓｅｄ　ｓｉｇｎｉｆｉｃａｎｔｌｙ　ｂｙ　ｐｌａｎｔｉｎｇ　ｏｎ　ｂａｒｅ　ｓａｎｄ，ｗｈｅｒｅａｓ　ｔｈｅ　ｐｅｒｃｅｎｔａｇｅ　ｏｆ　Ｃｏｃｔｏ　Ｃｔｏｃｈａｄ　ｎｏ　ｃｈａｎｇｅ．Ｒｏｂｉｎｉａ　ｐｓｅｕｄｏａｃａｃｉａ （ＲＰ），Ｈｅｄｙｓａｒｕｍ　ｓｃｏｐａｒｉｕｍ （ＨＳ），Ｓａｂｉｎａ　ｖｕｌｇａｒｉｓ （ＳＶ）ａｎｄ　Ｐｉｎｕｓ　ｓｙｌｖｅｓｔｒｉｓ　ｖａｒ．ｍｏｎｇｏｌｉｃａ （ＰＳ）ｉｍｐｒｏｖｅｄ　ｓｏｉｌ　ｑｕａｌｉｔｙ　ａｎｄ　ｃａｒｂｏｎ　ａｃｔｉｖｉｔｙ　ｍｏｒｅ　ｓｉｇｎｉｆｉｃａｎｔｌｙ　ｃｏｍｐａｒｅｄ　ｗｉｔｈ　ｏｔｈｅｒ　ｖｅｇｅｔａｔｉｏｎｓ．Ｓｅｎｓｉｔｉｖｅ　ｉｎｄｅｘ　ｓｈｏｗｅｄ　ｔｈａｔ　ｔｈｅ　ｆｉｒｓｔ（Ｃｆｒａｃ１）ａｎｄ　ｓｅｃｏｎｄ　ｆｒａｃｔｉｏｎ（Ｃｆｒａｃ２）ｏｆ　Ｃｏｃｈａｄ　ｈｉｇｈ　ａｃｔｉｖｉｔｙ，Ｃｆｒａｃ１ｗａｓ　ｍｏｒｅ　ｌａｂｉｌｅ　ｔｈａｎ　Ｃｆｒａｃ２ａｎｄ　ｃａｎ　ｂｅ　ｕｓｅｄ　ｔｏ　ｅｖａｌｕａｔｅ　ｓｏｉｌ　ｑｕａｌｉｔｙ．Ｃｏｒｒｅｌａｔｉｏｎ　ａｎａｌｙｓｉｓ　ｓｈｏｗｅｄ　ｔｈａｔ　ｔｈｅｒｅ　ｗａｓ　ａ　ｓｉｇｎｉｆｉｃａｎｔ　ｒｅｌａｔｉｏｎｓｈｉｐ　ａｍｏｎｇ　Ｃｆｒａｃ１，Ｃｆｒａｃ２，Ｃｆｒａｃ３，Ｃｆｒａｃ４，Ｃｏｃａｎｄ　Ｃｔｏｃ（Ｐ＜０．０１），ａｎｄ　ｔｈｅｙ　ｗｅｒｅ　ｐｏｓｉｔｉｖｅｌｙ　ｃｏｒｒｅｌａｔｅｄ　ｗｉｔｈ　ａｖａｉｌａｂｌｅ　Ｎ　ａｎｄ　ｔｏｔａｌ　Ｎ （Ｐ＜０．０５），ｂｕｔ　ｎｏｔ　ｃｏｒｒｅｌａｔｅｄｗｉｔｈ　ｔｏｔａｌ　Ｐ　ａｎｄ　ａｖａｉｌａｂｌｅ　Ｐ．Ａｄｄｉｔｉｏｎａｌｌｙ，Ｃｆｒａｃ４ａｎｄ　Ｃｔｏｃｗｅｒｅ　ｐｏｓｉｔｉｖｅｌｙ　ｃｏｒｒｅｌａｔｅｄ　ｗｉｔｈ　ａｖａｉｌａｂｌｅ　Ｐ（Ｐ＜０．０１）．Ｔｈｅｒｅ　ｗａｓ　ａ　ｎｅｇａｔｉｖｅ　ｃｏｒｒｅｌａｔｉｏｎ　ｂｅｔｗｅｅｎ　Ｃｆｒａｃ１，Ｃｆｒａｃ２，Ｃｆｒａｃ４，Ｃｏｃ，Ｃｔｏｃａｎｄ　ｐＨ　ｖａｌｕｅ（Ｐ＜０．０１ｏｒＰ＜０．０５）．Ｉｎ　ｃｏｎｃｌｕｓｉｏｎ，Ｃｆｒａｃ１ｃａｎ　ｂｅ　ｕｓｅｄ　ａｓ　ａ　ｆａｖｏｒａｂｌｅ　ｉｎｄｉｃａｔｏｒ　ｆｏｒ　ｓｏｉｌ　ｑｕａｌｉｔｙ　ｅｖａｌｕａｔｉｏｎ．Ｒｏｂｉｎｉａｐｓｅｕｄｏａｃａｃｉａ （ＲＰ），Ｈｅｄｙｓａｒｕｍ　ｓｃｏｐａｒｉｕｍ （ＨＳ），Ｓａｂｉｎａ　ｖｕｌｇａｒｉｓ （ＳＶ），ａｎｄ　Ｐｉｎｕｓ　ｓｙｌｖｅｓｔｒｉｓ　ｖａｒ．ｍｏｎｇｏｌｉｃａ（ＰＳ）ｃａｎ　ｂｅ　ｃｏｎｓｉｄｅｒｅｄ　ａｓ　ｐｒｅｆｅｒｅｎｔｉａｌ　ｃｈｏｉｃｅ　ｆｏｒ　ｓｏｉｌ　ｑｕａｌｉｔｙ　ｒｅｓｔｏｒａｔｉｏｎ　ｉｎ　Ｍｕｕｓ　ｓａｎｄｌａｎｄ

气缸盖气门座激光强化工艺

本发明公开了一种气缸盖气门座激光强化工艺，气缸盖气门座强化工艺，具体步骤为：1)对待处理气缸盖气门座进行清洗预处理；2)将气缸盖气门座划分不同处理区域，根据处理区域、气门座的不同和所需处理后气门座的硬度值调整激光处理参数；3)根据步骤2)的处理参数对气门座进行激光强化处理；4)处理完毕，对气门座进行辅助降温。采用本发明提供的气缸盖气门座激光强化工艺，可使气门座达到高耐磨性要求，符合现代发动机高功率密度、高紧凑和轻量化特点

1.48μm掺铒光纤放大器泵源

用P型InP衬底新月型(PBC)结构制备1.48μm大功率激光,与单模光纤耦合输出功率大于40mW

Laser surface hardening of 42CrMo cast steel for obtaining a wide and uniform hardened layer by shaped beams

For laser surface hardening (LSH) of large-sized workpieces, a wide and uniform hardened layer of a single track is pursued. In this study, two kinds of shaped laser beams were used in LSH of 42CrMo cast steel to obtain the required hardened layer. One is a stripy spot with uniform-intensity array spots and the other a stripy spot with intensity blowup in the edge of the whole array spots. As a comparison, a Gaussian laser beam was also adopted. A three-dimensional finite element model was used to simulate the thermal history of specific points by the latter shaped beam and the Gaussian laser beam. The surface morphology, microstructure, microhardness, and uniformity of hardened layers were studied. The results showed that a wider and more uniform hardened layer could be obtained using the latter shaped beam at relative higher scanning velocities and laser power. The thermal history of a material has an important effect on the microstructure and microhardness finally formed. Due to the high peak temperature and heating rate caused by the latter shaped beam, a higher value of microhardness in the transformation hardened zone was found

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies