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11.
石筠 《吉林化工学院学报》2021,38(4):52-56
吉林省红色资源作为中华民族精神的重要组成部分,是吉林省得天独厚的历史与人文资源,是优秀文化和优秀民族精神的延续,对当代大学生爱国主义教育开展的作用不容小觑。通过对吉林省爱国主义教学资源的梳理和挖掘,打造吉林省红色资源IP,多渠道加以利用,从而达到提高大学生爱国主义教育实效性的教学目标,培育大学生爱国主义精神。 相似文献
12.
Nadezhda A. Evtushenko Arkadii K. Beilin Erdem B. Dashinimaev Rustam H. Ziganshin Anastasiya V. Kosykh Maxim M. Perfilov Alexandra L. Rippa Elena V. Alpeeva Andrey V. Vasiliev Ekaterina A. Vorotelyak Nadya G. Gurskaya 《International journal of molecular sciences》2021,22(8)
The recessive form of dystrophic epidermolysis bullosa (RDEB) is a crippling disease caused by impairments in the junctions of the dermis and the basement membrane of the epidermis. Using ectopic expression of hTERT/hTERT + BMI-1 in primary cells, we developed expansible cultures of RDEB fibroblasts and keratinocytes. We showed that they display the properties of their founders, including morphology, contraction ability and expression of the respective specific markers including reduced secretion of type VII collagen (C7). The immortalized keratinocytes retained normal stratification in 3D skin equivalents. The comparison of secreted protein patterns from immortalized RDEB and healthy keratinocytes revealed the differences in the contents of the extracellular matrix that were earlier observed specifically for RDEB. We demonstrated the possibility to reverse the genotype of immortalized cells to the state closer to the progenitors by the Cre-dependent hTERT switch off. Increased β-galactosidase activity and reduced proliferation of fibroblasts were shown after splitting out of transgenes. We anticipate our cell lines to be tractable models for studying RDEB from the level of single-cell changes to the evaluation of 3D skin equivalents. Our approach permits the creation of standardized and expandable models of RDEB that can be compared with the models based on primary cell cultures. 相似文献
13.
《中国稀土学报(英文版)》2022,40(5):709-716
A series of new oxyapatite red phosphors Ca3Y7(BO4)(SiO4)5O doped with different concentrations of Eu3+ were successfully synthesized by high temperature solid state method. The X-ray diffraction (XRD) Rietveld refinement results show that the structure of the phosphor belongs to space group P63/m and Eu3+ ion replaces Y3+ ion. The emission spectrum consists of the characteristic emission peaks corresponding to Eu3+ under the excitation of 274 nm and the dominant emission peak is at 614 nm (5D0→7F2 of Eu3+). The concentration quenching effect occurs and the optimized Eu3+ concentration is 4.0 mol%. The energy level diagram for luminous mechanism is also given and the non-radiative energy transfer mechanism between Eu3+ is mainly exchange interaction. The CIE coordinate is close to the ideal red light and the color purity is higher than 99.79%. Moreover, the phosphor exhibits moderate thermal stability because the photoluminescence intensity at 423 K is still maintained at higher than 78.97% of that at room temperature. The internal quantum efficiency of Ca3Y7(BO4)(SiO4)5O:4.0 mol%Eu3+ phosphor is 58.2%. A red light emitting diode (LED) device based on it can emit bright red light. The CCT values of the device are basically unchanged when driven by various bias current. The results show that Ca3Y7(BO4)(SiO4)5O:Eu3+ is a new type of oxyapatite red fluorescent material with good comprehensive performances. 相似文献
14.
详细叙述了铅釉熔块的配料及熔制过程,按照熔块与Cr2O3的不同比例配制了釉料,通过对铅釉样品的讨论,弄清了Cr2O3在铅釉中的呈色特点,给出了红色铅釉和黄色铜釉的最佳配方。 相似文献
15.
16.
目的研制用于ABO、RHD血型检测试剂的红细胞瞬间磁化试剂。方法采用共沉淀法制备磁性粒子,并检测其主要成分及粒径大小,用此磁性粒子制备红细胞瞬间磁化试剂,并分别进行各项检测。结果磁性粒子的主要成分为四氧化三铁,粒径100nm左右。该试剂的外观及特异性均合格,磁响应时间不超过30s,重复性较好,敏感性为98.20%,与试管法检测结果比较,差异无显著意义。结论红细胞瞬间磁化试剂可用于红细胞系统的血型检测。 相似文献
17.
新型环氧防腐涂料的研究 总被引:1,自引:0,他引:1
采用在环氧树脂中加入纳米复合铁钛粉防锈颜料WD—D-325、固化剂、制备了新型环氧树脂防腐涂料。由于纳米技术的特性,该防腐涂料具有较高的防腐性、优异的附着力和柔韧性。实验确定了复合铁钛粉防锈颜料在环氧防腐涂料中的添加量。作为新型的环保颜料,复合铁钛粉防锈颜料可以替代红丹、锌铬黄等颜料。 相似文献
18.
Ioannis Lambropoulos Ioannis G. Roussis 《European Journal of Lipid Science and Technology》2007,109(6):623-628
The antioxidant activity of Xinomavro red wine phenolic extracts in corn oil stripped of tocopherols was evaluated. One wine extract, at 100 mg/L total phenolics, rich in phenolic acids and flavonols, inhibited the oxidation of corn oil stripped of tocopherols to a greater extent than butylated hydroxyanisole, at 200 mg/L. Moreover, another extract, at 100 mg/L total phenolics, rich in flavanols, flavonols and tyrosol, also exhibited high inhibitory action. The present results indicate that some red wine phenolics – such as phenolic acids, flavonols or flavanols – may be strong antioxidants in corn oil. 相似文献
19.
This paper presents a series of dendrimers via a convergent synthetic approach with three generations, which contain perylene diimide cores, Fréchet-type poly(aryl ether) dendrons, and carbazole (CZ) or oxadiazole (OXZ) peripheral functional groups. The higher generation dendrimer has an obvious site-isolation or dilution effect of dendrons, which results in a relatively small red-shift of absorption and emission spectra when it forms a solid thin film for applications. The interactions between peripheral units and perylene diimide core in the dendrimers are also studied by steady-state and time-resolved fluorescence spectra under both direct and indirect excitation. The fluorescence data show that there exist two possible mechanisms, Förster energy transfer (FRET) and photo-induced electron transfer (PET), for dendrimers bearing carbazole units. No enhanced core fluorescence is observed because the energy transfer or light-harvesting potential of peripheral carbazole is counteracted by PET. While for dendrimers bearing oxadiazole units, no PET can take place between OXZ and perylene diimide since both of them are high electron affinity. The FRET and higher light-harvesting ability of oxadiazole without PET interfering result in the distinct enhancement of core emission in higher generation dendrimers. DSC results indicate that the incorporation of Fréchet-type poly(aryl ether) dendrons can improve the amorphous property and increase glass transition temperature (Tg). The preliminary EL results with single-layer architectures demonstrate that these dendrimers could be utilized as a promising kind of active red luminescent emitters with carrier-transporting ability. EL emission has the same recombination zone as PL, indicating that the recombination of excitons in fabricated EL devices is not close to cathode or anode vicinity. It is suggested that the site-isolation effect of dendron wedges is attributed to prevent the core luminorphores from approaching electrodes efficiently. 相似文献
20.
A centrifugal sedimentation method (CSM) is proposed for the assessment of deformability of red blood cells. The method is based on the premise that a red blood cell (RBC) should deform in a centrifugal field due to the variation of the centrifugal acceleration with the distance from the center of rotation. This change in shape of the RBC leads to a change in the rate of sedimentation in the centrifugal field. The rate of sedimentation, which serves as a measure of deformability, is characterized by an apparent sedimentation coefficient (ASC) and its normalized value (NASC), which is calculated by comparison with a control group of normal RBCs. It has been shown that the NASC is sensitive to the speed of rotation, to treatments with glutaraldehyde, diamide, or chlorpromazine, to heat treatment and to osmotic pressure variations. 相似文献