六道沟小流域地形序列土壤碳剖面分布特征及影响因素

为了更好地理解黄土高原植被恢复与生态重建过程对土壤碳循环过程的影响，研究选取位于黄土高 原六道沟小流域的典型土壤地形序列（东北坡ＮＥ序列，西坡Ｗ 序列），分析了不同坡向间及同一坡向内随 植被类型变化土壤有机碳和无机碳的剖面分布特征及其影响因素。结果表明：六道沟小流域地形序列土 壤有机碳含量在０&mdash;５０ｃｍ土层内随土层深度增加而显著降低，５０ｃｍ土层以下基本趋于稳定，且剖面上层 （０&mdash;５０ｃｍ）有机碳含量显著高于剖面下层（５０&mdash;２００ｃｍ，ｐ＜０．０５），但在同一深度土层（０&mdash;５０，５０&mdash;２００， ０&mdash;２００ｃｍ）不同坡向林地和草地土壤有机碳平均含量均没有显著差异（ｐ＞０．０５）。与有机碳相比，无机碳 含量相对较高并且主要在剖面下部（５０ｃｍ以下）不同深度土层富集。ＮＥ序列林地和草地剖面无机碳平 均含量接近（ｐ＞０．０５），而Ｗ 序列林地剖面无机碳平均含量显著高于草地（ｐ＜０．０５）；不同坡向草地剖面 无机碳平均含量无显著差异（ｐ＞０．０５），但不同坡向林地剖面无机碳平均含量表现为Ｗ 序列显著高于ＮＥ 序列（ｐ＜０．０５）。０&mdash;５０ｃｍ土层有机碳含量与ｐＨ、容重和土壤含水量均呈极显著负相关关系，而与土壤 总孔隙度呈极显著正相关关系；５０&mdash;１５０ｃｍ土层无机碳含量与ｐＨ 和土壤总孔隙度均呈极显著负相关关 系，而与容重、黏粒含量和土壤含水量均呈极显著正相关关系。ＮＥ序列和Ｗ 序列２ｍ 土体总碳密度相 当，分别为１５．２～４７．４ｋｇ／ｍ２ 和１８．３～５１．３ｋｇ／ｍ２，其中无机碳密度占７８％～９４％，１&mdash;２ｍ土层总碳密 度占２ｍ土体总碳密度的３５％～７４％。若只考虑土壤有机碳库或只考虑浅层１ｍ土壤碳库，六道沟小流 域２ｍ土体总碳储量平均将被低估８８％和５１％。</p

茶多酚锰合成、表征及络合和诱导肿瘤细胞凋亡的研究

合成了茶多酚锰(TP-Mn)和茶多酚锗(TP-Ge),并采用红外光谱法及液相色谱质谱联用技术表征TP-Mn的理化特性.选用反向液相色谱(RP-HPLC)和电感藕合等离子体质谱(ICP-MS)技术研究牛血清白蛋白(BSA)络合TP-Mn的能力,指出BSA可直接络合于TP-Mn.采用MTT法研究TP和TP-Mn诱导Hela卵巢癌细胞的凋亡率.结果表明,TP和TP-Mn均能诱导Hela卵巢癌细胞凋亡,但TP-Mn诱导凋亡率约为TP的2倍.比较TP-Ge和TP-Mn诱导Raji人B淋巴瘤细胞凋亡率发现,两者诱导肿瘤细胞的凋亡率几乎相同,均高达86%左右.人血清白蛋白(HSB)可作为输送TP-Ge和TP-Mn的药物载体

基于层状氢氧化物衍生复合氧载体的生物质化学链气化实验研究

通过低饱和共沉淀法合成了类水滑石结构的层状氢氧化物（Layered Double Hydroxide,LDH）前驱体,经煅烧获得衍生Cu/Al/Zn、Cu/Al/Ni、Cu/Al/Ni/Zn高分散复合氧载体。采用XRD、XRF、H2-TPR、SEM及BET等分析手段对氧载体的结构及反应性能进行了表征,并通过固定床反应器开展了氧载体与生物质化学链气化实验。结果表明,合成的三种前驱体都具有典型的水滑石特征衍射峰,且层板稳定。Cu/Al/Zn前驱体层间厚度为0.264 2 nm,Ni2＋引入后,层间距减小。前驱体煅烧后形成的复合氧载体中元素含量与制备试剂基本一致。氧载体中Zn、Ni元素的引入可提升Cu O的反应活性,降低H2还原的反应温度,Zn元素与Cu具有更好的协同作用。Cu/Al/Ni/Zn氧载体在固定床化学链气化中具有较好的碳转化率和气体产率,其碳转化率为82.03%。反应后氧载体比表面积为5.995 m2/g,具有较好的可再生性与抗烧结性,是生物质化学链气化反应较为理想的氧载体

Chemical looping gasification of biomass based on the oxygen carrier derived from the layered double hydroxide（LDH） precursor

Layered double hydroxide（ LDH） precursors with different metal elements were prepared by co-precipitation method at constant p H value; highly dispersed Cu / Al / Zn,Cu / Al / Ni and Cu / Al / Ni / Zn mixed metal oxygen carriers were obtained by calculat

Synthesis, characterization and binding of tea polyphenol-manganese and apoptosis rate of induced tumor cells

【中文摘要】合成了茶多酚锰(TP-Mn)和茶多酚锗(TP-Ge),并采用红外光谱法及液相色谱质谱联用技术表征TP-Mn的理化特性.选用反向液相色谱(RP-HPLC)和电感藕合等离子体质谱(ICP-MS)技术研究牛血清白蛋白(BSA)络合TP-Mn的能力,指出BSA可直接络合于TP-Mn.采用MTT法研究TP和TP-Mn诱导Hela卵巢癌细胞的凋亡率.结果表明,TP和TP-Mn均能诱导Hela卵巢癌细胞凋亡,但TP-Mn诱导凋亡率约为TP的2倍.比较TP-Ge和TP-Mn诱导Raji人B淋巴瘤细胞凋亡率发现,两者诱导肿瘤细胞的凋亡率几乎相同,均高达86%左右.人血清白蛋白(HSB)可作为输送TP-Ge和TP-Mn的药物载体.【Abstract】Both tea polyphenol-manganese(TP-Mn) and germanium (TP-Ge) were synthesized with organic synthesis approaches. The characterizations of TP-Mn were clearly revealed via infrared spectrometry and HPLC-ESI-Q-TOF mass spectrometry, respectively. Both HPLC and ICP-MS methods were employed to study the capacities for bovine serum albumen (BSA) binding to TP-Mn, indicating these capacities feasibility. Apoptosis rates in Hela ovarian induced with TP and TP-Mn were studied by a 3-(4,5-dimethylthiazol-2-yl)2,5-diphenly tetrazolium. bromide(MYF) method. The experimental results show that both TP and TP-Mn can induced the cancer cell apoptosis, but the apoptosis rate with TP-Mn showed two times higher than that with TP. As compared experiments, the same apoptosis rates, going with up to approximately 86%, in Raji human B lymphoma induced with both TP and TP-Mn were observed directly. Human serum albumen might be employed to be a pharmacy carrier for transferring TP-Mn and TP-Ge in vivo.国家自然科学基金(批准号:30470372)、 厦门市科技项目 (批准号:3502Z2001263)和三明市科技项目(批准号:2004- L-1)资助

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