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41.
红四方面军从入川建立川陕革命根据地到出川北上抗日,面临的主要敌人就是四川各路军阀。四川军阀的态势,时刻影响着敌我战略格局。怎样利用军阀与军阅之间的矛盾开展斗争,成为关乎红四方面军和川陕革命根据地成败的重要因素。深入考察四川军阀态势对川陕革命根据地的创建、巩固、撤离过程的影响,可以获得有益的历史经验和教训。 相似文献
42.
WU Liting XIN Yujia GUO Zhaoyang GAO Wei ZHU Yanpeng br WANG Yinsong RAN Ruixue YANG Xiaoying 《高等学校化学研究》2022,38(2):562-571
Combining photothermal therapy and radiotherapy(PTT-RT) with reducing tumor hypoxia acts as an important antitumor modality. However, it is a great challenge to realize photothermal therapy, radiotherapy and exogenous oxygen supply in one nanosystem. To realize a combination of the three functions, we fabricated a red blood cell membrane(RBCm)-camouflaged, red blood cell content(RBCc) and the copper sulfide(CuS) co-loaded dendritic large pore mesoporous silica nanoparticle(DLMSN/CuS/RBCc/ RBCm). The cell membrane coating endowed the nanoparticles with good stability in the physiological environment, and CuS allowed the nanoparticle exhibiting good photothermal and radiosensitization properties. RBCc loaded nanoparticle DLMSN/CuS/RBCc enhanced superior anti-tumor effect than DLMSN/CuS during combined PTT-RT therapy because the introduction of RBCc increased the exogenous oxygen supply. The in vitro study further demonstrated that the combination of photothermal therapy and radiotherapy induced superior antitumor efficacy than single therapy. Our work thus presents a unique multifunctional nanoscale platform favorable for combined PTT and RT. 相似文献
43.
在对厚板材加工中存在的合理截断问题进行分析的基础上,以提高主产出材率为目的,提出了解决其现场操作的方法——采用红色激光器确定截断位置,并利用生产实际进行加工实验加以论证.实验表明:红色激光器对节子厚板材在截断时的主产出材率的提高效果十分显著. 相似文献
44.
以邻苯二胺、 2,5-二氨基苯磺酸和三氯化铝为原料, 通过无溶剂法大量制备了高效的红色荧光碳点 (R-CDs). 制得的碳点尺寸大约为2.4 nm, 含有13%的氮元素, 主要由高度石墨化的碳核及覆盖在其表面的大量官能团构成. 在不同的波长光激发下, 碳点在乙醇溶液中表现出不依赖于激发的红光发射, 其荧光峰位于 704 nm, 最大量子产率达到22%. 由于R-CDs具有优异的光学性质, 利用其构筑了紫外光激发的碳基白色发光二极管, 其色坐标为(0.33, 0.33), 非常接近自然光. 该研究为高效红色荧光碳点的大量制备提供了一种新路径, 同时拓宽了其在白光器件中的应用. 相似文献
45.
Take the cores and surface weathered soil from the Cretaceous red beds in the western of Dongshengmiao mine of Inner Mongolia and analysis with near-infrared spectroscopy. The result shows that near-infrared spectroscopy can identify mineral quickly through the characteristic absorption peaks of each group. The Cretaceous red beds in the western of Dongshengmiao mine is argillaceous cementation, it is mainly composed of quartz, feldspar, montmorillonite, illite, chlorite, muscovite etc, the mineral composition is mainly affected by the upstream source area. The clay mineral like montmorillonite water swelling and uneven drying shrinkage expands the original crack and creates new cracks, reduces its strength, which is the mainly reason of its disintegration. According to the composition of clay mineral, we speculate its weathering process is mainly physical weathering, the climate during the weathering is cold and dry. The results can not only improve the geological feature of the mining area, but also show that the near-infrared spectroscopy technology can analyze the mineral composition of soil and rock effectively on the basis of Mineral spectroscopy, which demonstrates the feasibility of the near-infrared spectroscopy can analyze minerals in soil and rock quickly, that shows the feasibility in geology study, provides new ideas for the future research of soil and rock. 相似文献
46.
《Current Applied Physics》2015,15(3):248-252
Red phosphors Ca9Bi1-x(PO4)7:xEu3+ (x = 0.06, 0.10, 0.20, 0.30, 0.40, 0.50, 0.60, 0.70, 0.80 and 1.00) were synthesized by a conventional solid-state reaction (SSR) route. The X-ray diffraction patterns, photoluminescence spectra, ultraviolet–visible reflection spectroscopy, decay time and the International Commission on Illumination (CIE) chromaticity coordinates of these compounds were characterized and analyzed. The Eu-doped Ca9Bi(PO4)7 phosphors exhibited strong red luminescence which peaks located at 615 nm due to the 5D0→7F2 electric dipole transition of Eu3+ ions after excitation at 393 nm. Ultraviolet–visible spectra indicated that the band-gap of Ca9Bi0.30(PO4)7:0.70Eu3+ is larger than that of Ca9Bi(PO4)7. The results indicate that the phosphor Ca9Bi0.30(PO4)7:0.70Eu3+ can be a suitable red-emitting phosphor candidate for LEDs. 相似文献
47.
李效文 《贵州师范大学学报(社会科学版)》2011,(5):82-85
在红色题材影视创作的书写系统中,贵州被加工成梦幻奇观、英雄神话的空间固然能够为受众提供某种程度上的观赏性消费满足,但是,决不应该让视听文本里的"西部空间"失去自治性、多样性的可能去受控于市场操作的过程;贵州不应是一个从现实中被抽离出来并放置到梦幻和神话表意系统中的、抽象的、空洞的符号,而应是一个建立在现实地理空间基础上的、具有区域特征和民族文化特色的、历史与现实相生的人文系统。 相似文献
48.
油菜叶片的光谱特征与叶绿素含量之间的关系研究 总被引:7,自引:1,他引:6
叶绿素是作物生长中的重要因素,是植物营养胁迫、光合作用能力和生长状况的良好指示剂。实时、可靠的作物营养诊断是进行科学施肥管理的基础,也是实践精细农业的关键技术之一。采用便携式可见-近红外光谱仪,在室外自然光照条件下对不同氮肥水平下油菜叶片的光谱特性进行了研究,并根据作物特有的光谱特征,采用逐步回归分析方法建立了油菜叶片的叶绿素含量与红边位置和绿峰位置之间的定量分析模型。结果表明,将红边位置、绿峰位置二者作为自变量时,建立的模型效果优于采用单一的红边位置为自变量时建立的模型效果。其相关系数分别为0.863和0.848;校正标准偏差SEC分别为5.273和5.459, 说明采用红边位置和绿峰位置这两个参数更能很好地预测叶片的叶绿素含量。 相似文献
49.
Fumiyoshi Ikkai Mitsuhiro Shibayama Shunji Nomura Charles C. Han 《Journal of Polymer Science.Polymer Physics》1996,34(5):939-945
Mesoscopic structures of poly(vinyl alcohol)(SINGLEBOND)Congo red (PVA(SINGLEBOND) CR) complexes in aqueous solutions were investigated in terms of dynamic light scattering (DLS) technique. The intensity-intensity time correlation function, g(2)(t), was analyzed with an equation including a single and a stretched exponential function. Two diffusion coefficients, Df (fast) and Ds (slow) were evaluated. Df was converted to the apparent correlation length, ξapp, via the mode-mode coupling hypothesis. The estimated ξapp was insensitive to the sol(SINGLEBOND)to(SINGLEBOND)gel transition but decreased with CR concentration. This change may be related to the electrostatic screening effect. On the other hand, Ds oscillates with increasing CR concentration at a specific PVA concentration range. This explains well the reentrant sol(SINGLEBOND)gel(SINGLEBOND)sol(SINGLEBOND)gel transition behavior observed in the PVA(SINGLEBOND)CR systems. Ds seems to represent the mobility of the PVA(SINGLEBOND)CR complexes, which annihilates at the gel point. © 1996 John Wiley & Sons, Inc. 相似文献
50.