Synthesis of (Ca, Mg)-α′-Sialon-AlN-BN powders from boron-rich blast furnace slag by microwave carbothermal reduction-nitridation

(Ca, Mg)-α′-Sialon-AlN-BN powders were synthesized by the carbothermal reduction and nitridation (CRN) method using boron-rich slag, one of the intermediate products from pyrometallurgy separation of pageit, as the staring material. The influences of synthesis temperature and holding time on the phase composition and microstructure during the microwave CRN were studied by XRD, SEM and EDS. The comparison between two heating techniques, conventional and microwave heating, on the synthesized powder was presented as well. The experimental results revealed that the phase compositions and microstructures of the synthesized products were greatly affected by the synthesis temperature and holding time. With an increase in the synthesis temperature or holding time, the relative amount of α′-Sialon increased and α′-Sialon became the main crystalline phase at 1400 °C for 6 h. The synthesized products also contained AlN, BN and a small amount of β-SiC. Elongated α′-Sialon grains, short rod AlN grains, aggregate nanoscale BN grains were observed in the synthesized powders. The reaction temperature of microwave heating method was reduced by 80 °C, the reaction time was shortened by 2 h, and more elongated α′-Sialon grains with large aspect ratio were observed.

Microwave-assisted Green and Efficient Synthesis of N^6-(2-Hydroxyethyl)adenosine and its Analogues

An efficient protocol for the synthesis of N^6-（2-Hydroxyethyl）adenosine and its analogues through nucleophilic substitution was developed. All the reactions were completed in 10 rain under microwave irradiation. Using water as solvent makes our method eco-friendly and easy to handle with.

Microwave promoted one-pot synthesis of 3-(2′-amino-3′-cyano-4′-arylpyrid-6′-yl)coumarins

A facile procedure for the synthesis of 3-（2′-amino-3′-cyano-4′-arylpyrid-6′-yl） coumarins are being reported starting from 3- acetylcoumarin, aromatic aldehydes and malononitrile. The reactions were carried out on microwave irradiation in good yield with short time and easy work-up. The structures of all the compounds have been confirmed on the basis of their analytical, IR, ^1H NMR, and mass spectral data.

Quinacrine pretreatment reduces microwave-induced neuronal damage by stabilizing the cell membrane

Quinacrine, widely used to treat parasitic diseases, binds to cell membranes. We previously found that quinacrine pretreatment reduced microwave radiation damage in rat hippocampal neurons, but the molecular mechanism remains poorly understood. Considering the thermal effects of microwave radiation and the protective effects of quinacrine on heat damage in cells, we hypothesized that quinacrine would prevent microwave radiation damage to cells in a mechanism associated with cell membrane stability. To test this, we used retinoic acid to induce PC12 cells to differentiate into neuron-like cells. We then pretreated the neurons with quinacrine （20 and 40 mM） and irradiated them with 50 mW/cm^2 microwaves for 3 or 6 hours. Flow cytometry, atomic force microscopy and western blot assays revealed that irradiated cells pretreated with quinacrine showed markedly less apoptosis, necrosis, and membrane damage, and greater expression of heat shock protein 70, than cells exposed to microwave irradiation alone. These results suggest that quinacrine stabilizes the neuronal membrane structure by upregulating the expression of heat shock protein 70, thus reducing neuronal injury caused by microwave radiation.

Optimization of Process Parameters of Continuous Microwave Drying Raspberry Puree Based on RSM and ANN-GA

To improve drying uniformity and anthocyanin content of the raspberry puree dried in a continuous microwave dryer,the effects of process parameters(microwave intensity,air velocity,and drying time)on evaluation indexes(average temperature,average moisture content,average retention rate of the total anthocyanin content,temperature contrast value,and moisture dispersion value)were investigated via the response surface method(RSM)and the artificial neural network(ANN)with genetic algorithm(GA).The results showed that the microwave intensity and drying time dominated the changes of evaluation indexes.Overall,the ANN model was superior to the RSM model with better estimation ability,and higher drying uniformity and anthocyanin retention rate were achieved for the ANN-GA model compared with RSM.The optimal parameters were microwave intensity of 5.53 W•g^(-1),air velocity of 1.22 m·s^(-1),and drying time of 5.85 min.This study might provide guidance for process optimization of microwave drying berry fruits.

Microwave absorption properties regulation and bandwidth formula of oriented Y_(2)Fe_(17)N_(3-δ)@SiO_(2)/PU composite synthesized by reduction-diffusion method

As concepts closely related to microwave absorption properties,impedance matching and phase matching were rarely combined with material parameters to regulate properties and explore related mechanisms.In this work,reduction–diffusion method was innovatively applied to synthesize rare earth alloy Y_(2)Fe_(17).In order to regulate the electromagnetic parameters of absorbers,the Y_(2)Fe_(17)N_(3-δ)particles were coated with silica(Y_(2)Fe_(17)N_(3-δ)@SiO_(2))and absorbers with different volume fractions were prepared.The relationship between impedance matching,matching thickness,and the strongest reflection loss peak(RLmin)was presented obviously.Compared to the microwave absorption properties of Y_(2)Fe_(17)N_(3-δ)/PU absorber,Y_(2)Fe_(17)N_(3-δ)@SiO_(2)/PU absorbers are more conducive to the realization of microwave absorption material standards which are thin thickness,light weight,strong absorbing intensity,and broad bandwidth.Based on microwave frequency bands,the microwave absorption properties of the absorbers were analyzed and the related parameters were listed.As an important parameter related to perfect matching,reflection factor(√ε_(r)/μ_(r))was discussed combined with microwave amplitude attenuation.According to the origin and mathematical model of bandwidth,the formula of EAB(RL<-10 dB)was derived and simplified.The calculated bandwidths agreed well with experimental results.

Microwave Synthesis and Crystal Structure of Bis{2-[(2,4-dichloro-phenylimino)methyl]-4,6-diiodo-phenol}-copper(Ⅱ)

Bis{2-[（2,4-dichloro-phenytimino）-methyl]-4,6-diiodo-phenol}-copper（II） （1） has been synthesized and its structure determined by X-ray diffraction. It crystallizes in the monoclinic system, space group P21/n with a = 14.7558（17）, b = 20.770（2）, c = 20.3260（19） A, β = 90.6110（10）°, V= 6229.2（11） A3 and Z = 8. The Cu atom is surrounded by two O atoms and two N atoms from two 2-[（2,4-diehloro-phenylimino）-methyl]-4,6-diiodo-phenol molecules to form a tetrahedral coordination environment. The complex is linked into a column by weak intermolecular interactions.

Microwave-accelerated direct regeneration of LiCoO_(2)cathodes for Li-ion batteries

Recycling spent lithium-ion batteries is integral to today's low-carbon environmental protection efforts.The concept of direct regeneration,acknowledged for its environmental sustainability,economic viability,and consistent performance of recycled materials,is gaining prominence.This study presents an efficient and nondestructive approach by utilizing an ultrafast microwave technology to directly regenerate spent lithium cobaltate(LCO)cathode materials.In contrast to conventional furnacebased processes,this method significantly reduces the regeneration timeframe.By subjecting the spent LCO mixed with lithium sources to three microwave heating cycles(at approximately 1,350 K),LCO regeneration is achieved,yielding a specific capacity of 140.8 mAh g^(-1)(0.2 C)with a robust cycle stability.With further environmental and economic benefits,the ultrafast microwave technology holds scientific promise for directly regenerating cathode materials,while establishing competitiveness for industrial applications.

微波-水蒸气法再生载亚甲基蓝废活性炭研究

基于微波的加热特性和活性炭的吸波性,探索出可行、有效的活性炭再生方法,能增加失效活性炭的重复使用率,节约废水处置经济成本。文章采用微波联合水蒸气法进行再生实验,以亚甲基蓝吸附值作为指标评估再生效果,设立单因素实验和三因素三水平正交实验,研究微波功率、微波时间以及蒸气流量对生物炭再生的影响规律,并对原炭、废炭和再生后活性炭开展X射线衍射表征。结果表明:微波功率对再生效果影响最大,且微波功率和蒸气流量越大,再生效果越好,但微波时间不宜过长,在微波功率为800 W、微波时间为15 min和蒸气流量为5 mL/min条件下,再生活性炭的再生率约为75%;微波加热可使吸附质热解,并且水蒸气可清理炭孔,使活性炭恢复到原有的吸附活性,再生活性炭的效果较好,且成本低,可应用到实际工程中。

Puerarin accelerates neural regeneration after sciatic nerve injury

Puerarin is a natural isoflavone isolated from plants of the genus Pueraria and functions as a protector against cerebral ischemia. We hypothesized that puerarin can be involved in the repair of peripheral nerve injuries. To test this hypothesis, doses of 10, 5, or 2.5 mg/kg per day puer- arin （8-（β-D-Glucopyranosyl-7-hydroxy-3-（4-hydroxyphenyl）-4H-l-benzopyran-4-one） were injected intraperitoneally into mouse models of sciatic nerve injury. Puerarin at the middle and high doses significantly up-regulated the expression of growth-associated protein 43 in the L4_6 segments of the spinal cord from mice at 1, 2, and 4 weeks after modeling, and reduced the atro- phy of the triceps surae on the affected side and promoted the regeneration of nerve fibers of the damaged spinal cord at 8 weeks after injury. We conclude that puerarin exerts an ongoing role to activate growth-associated protein 43 in the corresponding segment of the spinal cord after sciat- ic nerve injury, thus contributing to neural regeneration after sciatic nerve injuries.

T cells promote the regeneration of neural precursor cells in the hippocampus of Alzheimer's disease mice

Alzheimer＇s disease is closely associated with disorders of neurogenesis in the brain, and growing evidence supports the involvement of immunological mechanisms in the development of the disease. However, at present, the role of T cells in neuronal regeneration in the brain is unknown. We injected amyloid-beta 1-42 peptide into the hippocampus of six BALB/c wild-type mice and six BALB/c-nude mice with T-cell immunodeficiency to establish an animal model of Alzhei- mer＇s disease. A further six mice of each genotype were injected with same volume of normal saline. Immunohistochemistry revealed that the number of regenerated neural progenitor cells in the hippocampus of BALB/c wild-type mice was significantly higher than that in BALB/c-nude mice. Quantitative fluorescence PCR assay showed that the expression levels of peripheral T cell-associated cytokines （interleukin-2, interferon-y） and hippocampal microglia-related cyto- kines （interleukin-113, tumor necrosis factor-a） correlated with the number of regenerated neural progenitor cells in the hippocampus. These results indicate that T cells promote hippocampal neurogenesis in Alzheimer＇s disease and T-cell immunodeficiency restricts neuronal regeneration in the hippocampus. The mechanism underlying the promotion of neuronal regeneration by T cells is mediated by an increased expression of peripheral T cells and central microglial cytokines in Alzheimer＇s disease mice. Our findings provide an experimental basis for understanding the role of T cells in Alzheimer＇s disease.

Bumetanide promotes neural precursor cell regeneration and dendritic development in the hippocampal dentate gyrus in the chronic stage of cerebral ischemia

Bumetanide has been shown to lessen cerebral edema and reduce the infarct area in the acute stage of cerebral ischemia. Few studies focus on the effects of bumetanide on neuroprotection and neurogenesis in the chronic stage of cerebral ischemia. We established a rat model of cerebral ischemia by injecting endothelin-1 in the left cortical motor area and left corpus striatum. Seven days later, bumetanide 200 μg/kg/day was injected into the lateral ventricle for 21 consecutive days with a mini-osmotic pump. Results demonstrated that the number of neuroblasts cells and the total length of dendrites increased, escape latency reduced, and the number of platform crossings increased in the rat hippocampal dentate gyrus in the chronic stage of cerebral ischemia. These findings suggest that bumetanide promoted neural precursor cell regeneration, dendritic development and the recovery of cognitive function, and protected brain tissue in the chronic stage of ischemia.

Widely tunable microwave photonic filter based on self-adaptive optical carrier regeneration

In this paper, we have designed and proofed a widely tunable microwave photonic filter (MPF) on the basis of self-adaptive optical carrier regeneration method through stimulated Brillouin scattering (SBS) amplification. The MPF system features with a single microwave passband as the result of the processed signal sideband beating with the regenerated optical carrier. Since the Brillouin-laser optical carrier and the SBS amplification are generated from one laser source, the optical carrier regeneration process of the proposed MPF is self- adaptive and carrier-frequency independent. Moreover, by simply varying the wavelength spacing between the optical carrier and the optical filter, the central passband of the MPF can be continuously tuned from 6 to 32 GHz, which is limited by the bandwidth of the modulator and the photodetector. The 3 dB bandwidth and the out-of-band suppression ratio of the MPF can reach 640 MHz and 21 dB, respectively.

采用微波和铈-锰基添加剂的柴油机微粒捕集器复合再生的研究

利用所建立的泡沫陶瓷过滤体再生三维模型进行仿真,研究燃油中加入不同含量的铈锰添加剂对微粒捕集装置再生过程的影响,并进行了相关对比试验,试验结果与计算结果基本一致。结果表明:当铈锰元素含量之比为75:25时,过滤体再生时间最短。

微波消解-电感耦合等离子体原子发射光谱法测定氧化铁粉中14种元素

提出了微波消解电感耦合等离子体原子发射光谱(ICP-AES)同时测定酸再生氧化铁粉中铝、硅、硫、钙、锰、硼、钛、镁、钾、钠、磷、铬、镍、铜等14种元素的分析方法。采用微波消解技术消解酸再生氧化铁粉,考察了微波消解时间、功率和压力对消解效果的影响,选择了最佳工作参数。通过ICP-AES仪器的FACT软件,选择合适的分析谱线,避免了基体干扰和元素之间的光谱干扰。同时对溶样条件、基体影响的机理等进行了探讨。微波消解方法测量结果的回收率及相对标准偏差(n=6)均优于常规溶样方法。对酸再生氧化铁粉样品的测定结果与传统湿法分析的结果相一致。

微波活化赤泥对分散艳蓝E-4R的吸附去除研究

研究了赤泥对染料废水中分散艳蓝E-4R的吸附作用,结果表明,微波活化后赤泥具有良好的吸附效果,对分散艳蓝E-4R的吸附行为符合Langmuir等温方程。活化后赤泥对分散艳蓝E-4R的饱和吸附量为42.19mg/g,其中影响吸附效果的因素有赤泥投加量、温度和pH值。经过优化得到最佳条件:温度为40℃,pH值为3.0,赤泥投加量为15g/L。在最佳条件下,吸附时间为30min,活化赤泥第一次使用时对质量浓度为300g/L的分散艳蓝E-4R的脱色率、COD及TOC去除率分别达到99.07%、、64.08%和50%。经过3次使用后,赤泥对染料的吸附能力下降,经微波再生后吸附性能得到恢复。

微波-超声波联合再生活性炭及其用于处理含酚废水

利用微波-超声波联合工艺对吸附饱和的活性炭进行再生处理,并以苯酚溶液为含酚废水模型,采用正交实验探讨了微波、超声波功率和时间对活性炭再生效果的影响。实验结果表明,对活性炭再生的影响因素大小顺序为;微波功率>超声波功率>反应时间;在适宜的再生条件下(微波功率400 W、超声波功率200 W、反应时间4 min),活性炭再生效率可达95.8%。研究了再生处理前后的活性炭对苯酚的吸附行为,再生前的吸附行为符合Langmuir等温吸附模型,饱和吸附量为156.6 mg/g;再生后的吸附行为符合Freundlich等温吸附模型,为多层吸附。经微波-超声波联合工艺处理的再生活性炭对苯酚的吸附效率比单独使用微波或超声波处理分别提高了35%和200%。

微波-活性炭联合处理焦化废水的应用前景

焦化废水是一种有机物浓度较高且含氨氮很难降解的有机工业废水。本文介绍了目前国内外焦化废水的治理现状以及微波-活性炭处理技术应用的情况,讨论了微波-活性炭处理废水的机理,并对微波-活性炭协同深度处理工业废水的前景进行了展望。

甘氨酸母液脱色废活性炭的微波-Fenton试剂氧化法再生

采用微波-Fenton试剂氧化法对甘氨酸母液脱色过程中产生的废活性炭进行再生,考察了废活性炭再生率的影响因素,并用SEM对再生活性炭进行了表征。实验结果表明,在Fenton试剂中n(H2O2)∶n(Fe2+)为24∶1、H2O2的浓度为25 mmol/L、溶液pH为3、反应温度为55℃、反应时间为18 min、微波功率为600 W时,废活性炭的再生率可达到75.80%。

活性炭吸附-微波再生技术研究进展

综述了活性炭吸附-微波再生技术应用于环境污染治理方面的研究进展;阐述了微波再生的作用机理,提出了有待进一步研究的问题。众多实验表明:微波功率、辐照时间、活性炭吸附量等是影响再生活性炭吸附性能的主要因素。