Effects of Far-Infrared Irradiative Heating Pasteurization on Fungi

The effect of far-infrared (FIR) irradiation pasteurization on fungi was quantitatively evaluated and compared with the effect of thermal conductive heating. After the bulk temperature of the sterile saline irradiated by FIR reached a steady given temperature, yeast cells (Candida albicans NBRC 1950 and Saccharomyces cerevisiae NBRC 1067) or fungal spores (Aspergillus niger NBRC 4781) were inoculated and FIR heating was conducted. A mullite cylinder FIR heater, with a main wavelength of 4 - 7 μm, was used for FIR heating. Death of fungi by FIR heating and by thermal conductive heating both followed first-order reaction kinetics, and the apparent death rate constants under different temperature conditions were obtained. For the same bulk temperatures, pasteurization by FIR heating was more effective than thermal conductive heating. The activation energy for the death of fungi by FIR irradiation was slightly lower than thermal conductive heating, indicating differences in the mechanism of action.

Topological structure effect on far-infrared spectra in a GaAs/InAs nanoring

On the basis of the growth mechanism of a GaAs/InAs nanoring, we propose a fine model which reflects the confinement details of real nanoring. Through calculations of the two-electron energy and far-infrared （FIR） spectra, we find that the ring topological structure and electron-electron interaction have great influence on the FIR spectra. The two unknown transition peaks in the experiment are determined theoretically. The theoretical results are in good agreement with the experiments.

Adjustable polarization-independent wide-incident-angle broadband far-infrared absorber

To promote the application of far-infrared technology,functional far-infrared devices with high performance are needed.Here,we propose a design scheme to develop a wide-incident-angle far-infrared absorber,which consists of a periodically semicircle-patterned graphene sheet,a lossless inter-dielectric spacer and a gold reflecting film.Under normal incidence for both TE-and TM-polarization modes,the bandwidth of 90%absorption of the proposed far-infrared absorber is ranging from 6.76 THz to 11.05 THz.The absorption remains more than 90%over a 4.29-THz broadband range when the incident angle is up to 50◦for both TE-and TM-polarization modes.The peak absorbance of the absorber can be flexibly tuned from 10%to 100%by changing the chemical potential from 0 eV to 0.6 eV.The tunable broadband far-infrared absorber has promising applications in sensing,detection,and stealth objects.

Evaluation of electron-electron interactions in coupled quantum dots by using far-infrared spectra

We have studied the far-infrared spectra of two-electron vertically coupled quantum dots in an axial magnetic field by exact diagonalization. The calculated results show an obvious difference in role between the interactions for spin S = 1 and for spin S = O. The results support the possibility to evaluate the interactions by far-infrared spectroscopy in vertically coupled quantum dots.

Signature of symmetry of laterally coupled quantum dots in far-infrared spectrum

We study the effect of structure asymmetry on the energy spectrum and the far-infrared spectrum （FIR） of a lateral coupled quantum dot. The calculated spectrum shows that the parity break of coupled quantum dot results in more coherent superpositions in the low-lying states and exhibits unique anti-crossing in the two-electron FIR spectrum modulated by a magnetic field. We also find that the Coulomb correlation effect can make the FIR spectrum of coupled quantum dot without strict parity deviate greatly from Kohn theorem, which is just contrary to the symmetric case. Our results therefore suggest that FIR spectrum may be used to determine the symmetry of coupled quantum dot and to evaluate the degree of Coulomb interaction.

Non-Thermal Biological Effect of Graphene Far-Infrared Ray on Saccharomyces cerevisiae Cells

Graphene materials can emit far-infrared ray, but the biological effects of graphene far-infrared ray have not been studied. Furthermore, the non-thermal biological effect of far-infrared ray on organism has not been systematically studied independently of the thermal effect. The purpose of this study was to investigate the non-thermal biological effect of graphene far-infrared ray (gFIR) on Saccharomyces cerevisiae cells. In this work, stringent control of the cultivation conditions was carried out to ensure the stability and constancy of the culture and its temperature. Flow cytometry was used to detect the non-thermal effect of gFIR irradiation on cell membrane permeability, mitochondrial membrane potential (MMP) and intracellular reactive oxygen species (ROS) content. Compared with the control group, cell membrane permeability of the gFIR exposure cells decreased by 4.7%, MMP increased by 16% and intracellular ROS reduced by 10.7%. The results revealed the valuable features of the non-thermal biological effect of gFIR on Saccharomyces cerevisiae cells, and the further analysis demonstrated that graphene far-infrared materials should have great application value in disease prevention and health promotion.

〔C II〕Continuum Intensity Ratio in the Far-Infrared Toward the Central Kiloparsec of the Nearby Spiral Galaxy M31

We observed the nearby galaxy M31 in the 〔C II〕158 μm emission line. An extended component was detected over the central 1 5 kpc region with a line-to-continuum ratio of 〔C II〕/〔40-120μm〕6×10 -3 . This ratio is 3 times larger than that of the Galactic counterpart and is comparable to that in the general Galactic Plane. We expect that the difference between the two central regions are due to different gas densities; the self-shielding of CO molecules decreases the C + abundance at the higher density in the Galactic case.

Effect of Low Energy Far-Infrared Irradiation on Facial Skin for Healthy People

Objective: Utilizing VISIA skin tester to quantitatively evaluate the effect of low energy far-infrared irradiation on healthy people’s facial skin. Methods: 60 volunteers were selected in hospital from September 2019 to June 2020, and the total score of face, skin spots, texture, wrinkles and pores were observed before and after low energy far-infrared irradiation treatment with VISIA skin tester. Results: After 2 weeks of low energy far-infrared irradiation treatment, the total skin score of volunteers increased significantly (P < 0.01). In the itemized statistics, the moisture value, stain value and wrinkle value increased significantly (P < 0.05). Conclusion: Low energy far-infrared irradiation can significantly improve the facial skin quality of healthy people.

Preparation and Drug-Release Property of Polycaprolactone (PCL)/Polyglycolic Acid (PGA) Composite Masterbatch with Drug of Tea Polyphenols (TPs)

In order to effectively control the drug-release rate of medical textiles,biodegradable polycaprolactone(PCL) and polyglycolic acid(PGA) were blended at various mass ratios to prepare composite masterbatches for medical textiles.The surface morphology and the chemical structure of the masterbatches were analyzed.The crystallization,mass losses,strengths and drug-release rates of the composite masterbatches at different PCL/PGA mass ratios were explored.The results show that the degradation rate of the PGA carrier is obvious higher than that of the PCL carrier,and PCL,PGA and the tea polyphenol(TP) drug just physically mix without chemical reaction.During the degradation,the strength of the composite masterbatches gradually decreases.In addition,the drug-release rates of composite masterbatches at different mass ratios are different,and the more the PGA in the composite masterbatches,the faster the drug release of the composite masterbatches.The drug-release rate of the composite masterbatches can be controlled by adjusting the contents of PCL and PGA.

碱溶性聚酯/碳酸钙/聚酯(COPET/CaCO_(3)/PET)多孔纤维制备及性能研究

采用自制的碱溶性聚酯/碳酸钙(COPET/CaCO_(3))母粒与聚酯(PET)母粒,经熔融纺丝实现对传统PET纤维的改性,结合单因子控制变量法优选碱酸处理制备COPET/CaCO_(3)/PET多孔纤维的最佳工艺参数,并对纤维性能进行测试与表征。结果表明,当NaOH质量分数为4%、HCL质量分数为3%时,纤维具有较好的表观形态和孔隙结构。在最优处理条件下,纤维内部含有较多分布均匀的孔隙,孔径主要集中分布在15~54nm。此时,纤维的断裂强度、线密度、比表面积和熔融温度分别为1.29cN/dtex、4.84dtex、5.5273m^(2)/g和253.85℃。

ATPB超分散剂的合成及其在ABS/炭黑复合体系中的应用

以端羟基聚丁二烯和N,N-二甲基氨基丙胺为原料,采用两步亲核取代反应制备了含有聚丁二烯骨架和胺基末端结构的端胺基聚丁二烯(ATPB),利用傅里叶变换红外光谱仪、核磁共振氢谱仪表征其分子结构,结果表明,ATPB成功合成并达到预期分子结构。以ATPB为超分散剂,制备了丙烯腈-丁二烯-苯乙烯嵌段共聚物(ABS)和炭黑的复合材料,测试炭黑分散度、分散稳定性和复合材料力学性能。结果表明,合成的ATPB超分散剂对炭黑具有明显的分散效果和较好的分散稳定性,与未经分散的炭黑相比,体系分散度提高了65.8%。复合材料力学性能得到增强,拉伸、弯曲强度分别提升至45.56、78.31 MPa,冲击强度提高了15.7%,其值为7.50 kJ/m^(2)。

基于可低温加工SEBS的发泡母粒及微发泡热塑性弹性体的制备

以可低温加工的氢化苯乙烯-丁二烯嵌段共聚物(SEBS)为基体,将偶氮二甲酰胺(AC)发泡剂、助发泡剂和表面活性剂制备成基于SEBS的发泡母粒,并采用双螺杆挤出机将发泡母粒与动态硫化三元乙丙橡胶(EPDM)/聚丙烯(PP)热塑性弹性体材料(TPE)共混熔融挤出,制备了微发泡TPE材料。研究了SEBS引入量与发泡母粒添加量对微发泡TPE样品的密度、拉伸性能以及泡孔形貌的影响。结果表明,当SEBS的质量分数低于6%,发泡母粒的质量分数为3%时,制备的微发泡TPE材料具有较低的密度、较高的拉伸性能,且泡孔规整度达到最优。

无卤阻燃母粒及其改性纤维的制备和性能研究

以无卤阻燃剂为改性剂、大有光聚对苯二甲酸乙二酯(PET)切片为基体熔融挤出制得无卤阻燃母粒,并将其与半消光PET切片共混熔融纺丝得到阻燃PET预取向丝(POY),再经加弹得到阻燃PET拉伸变形丝(DTY),探究了加工工艺对阻燃母粒制备的影响,评价了阻燃母粒的物性指标和热稳定性,并研究了阻燃母粒添加量对纤维力学性能和阻燃性能的影响。结果表明:阻燃母粒的较佳制备工艺为阻燃剂质量分数40%、熔体温度265℃、螺杆转速200 r/min、切粒机转速35 Hz;阻燃剂在PET基体中均匀分散,加入后不影响PET切片的特性黏数和熔点等物性指标,且提高了PET的热稳定性和成炭能力;当添加的阻燃母粒质量分数为6%~12%时,制备的阻燃PET POY的力学性能与常规PET POY接近;当添加的阻燃母粒质量分数为10%时,制备的阻燃PET DTY具有优异的阻燃性能,极限氧指数达31.8%。

聚乙烯醇-乙烯/SiO 2复合柔性驱动膜的制备及其性能

针对当前柔性智能驱动材料在开发过程中存在的响应性差、制备工艺复杂、成本高、刺激源污染大等问题,采用分层喷涂法制得具有非对称结构的聚乙烯醇-乙烯共聚物(PVA-co-PE)/SiO 2双层复合柔性驱动膜,并对其表面形貌、亲疏水性、力学性能、驱动性能等进行表征与测试分析。结果表明:纳米纤维直径越小,越有利于SiO 2粉体在纳米纤维表面的附着,复合驱动膜的亲水性随着纳米纤维直径的增加呈现逐渐下降的趋势,同时纤维直径的增加可大幅提升复合驱动膜的拉伸应力;另外,随着纳米纤维直径从180 nm增加至390 nm,复合驱动膜的形变角度逐渐变小,且当复合驱动膜中纳米纤维直径为180 nm,SiO 2粉体粒径为15 nm时,制备的复合驱动膜具有最佳的驱动性能,在0.7 s左右即可达到180°的最大弯曲角度。基于该PVA-co-PE/SiO 2复合驱动膜快速的刺激响应性、大尺度的弯曲形变能力,其在智能操控、人工肌肉以及智能服装领域中具有较好的应用前景。

增韧聚醚酰亚胺(PEI)复合材料的制备及性能研究

采用三元乙丙橡胶(EPDM)、自主创新研发的聚苯乙烯基炭化微球、聚醚酰亚胺为原料,通过挤出熔融共混法制得增韧聚醚酰亚胺复合材料。实验结果表明,当加入三元乙丙橡胶用量为15份时,其冲击强度、断后伸长率与纯料进行对比,分别提高了200.0%、272.7%,达到了提高聚醚酰亚胺抗冲性能的目的;DSC测试结果表明,在聚苯乙烯基炭化微球作用下,三元乙丙橡胶与聚醚酰亚胺具有一定的相容性;TGA测试结果表明,聚醚酰亚胺复合材料加工温度在430℃范围内热稳定性良好;SEM冲击断面表明,EPDM/聚苯乙烯基炭化微球母粒料的加入对聚醚酰亚胺具有增韧效果,且粒子分布均匀。

高光泽PET管用黑色母粒的制备及性能研究

传统采用添加黑色母粒制备得到PET管光泽暗淡、不鲜艳,因此,提高黑色母粒的性能以制备得到光泽度高的PET管是目前急需解决的问题。本研究通过炭黑选型、分散剂用量以及添加一定量的与其折光指数相近的无机微粒硫酸钡(BaSO_(4)),分别考察炭黑、分散剂和BaSO_(4)对高光泽PET管用黑色母粒流动性、着色力和色彩性能的影响。实验结果表明:采用炭黑I,分散剂添加量为4%(质量分数),BaSO_(4)添加量1.5%(质量分数)制备的高光泽PET管用黑色母粒压滤值为0.44 MPa,着色力为104.7,光泽C*为0.7,综合性能最佳。

175 dtex原液着色涤纶预取向丝的制备工艺

采用特殊工艺共混改性路线和在线添加黑母粒技术,研制开发175 dtex原液着色涤纶预取向丝(POY)。对切片和黑母粒的干燥工艺、过滤、纺丝的油嘴选型、冷却条件、卷绕成型等生产工艺进行了研究,确定了175 dtex原液着色涤纶POY的最佳制备工艺,制得的产品综合性能良好,满足后道客户加工要求。

83 dtex/24 f阻燃尼龙66纤维的制备及性能研究

以相对黏度2.52的尼龙66切片为原料,以相对黏度2.75的阻燃母粒为改性剂,采用在线添加方式将阻燃母粒与尼龙66切片共混并熔融纺丝,制备83 dtex/24 f阻燃尼龙66纤维,分析了阻燃母粒的有效成分,着重研究了阻燃母粒添加量及纺丝温度对纤维阻燃性能及力学性能的影响。结果表明:阻燃母粒的基体为尼龙66,有效阻燃成分为氮和磷;随着阻燃母粒添加量的增加,纤维的极限氧指数(LOI)提高,但添加阻燃母粒质量分数大于5%后,LOI提升幅度不大,且可纺性变差;随着纺丝温度的提高,纤维断裂强度先增后降,在纺丝温度285℃时断裂强度达到最大;在添加阻燃母粒质量分数5%、纺丝温度285℃、纺丝速度3200 m/min、拉伸倍数2.7的较佳工艺条件下,制备的83 dtex/24 f阻燃尼龙66纤维具有良好的阻燃性能和力学性能,断裂强度为4.16 cN/dtex,LOI为32.3%。

涤纶染色和色母粒着色绒类产品碳足迹核算及评价

为了应对社会对披露碳足迹信息的要求,根据碳足迹核算标准,以1 t涤纶绒类产品为功能单位,分别计算涤纶染色绒类产品与涤纶色母粒着色绒类产品从摇篮到大门的碳足迹。结果表明:1 t涤纶染色产品从摇篮到大门的产品碳足迹为6483.8 kgCO_(2)e,1 t涤纶色母粒着色绒类产品从摇篮到大门的产品碳足迹为5217.8 kgCO_(2)e。相比同样功能的涤纶染色产品,每功能单位的涤纶色母粒着色绒类产品碳足迹减排率为19.5%。两款产品的碳排放主要来源于原料和能源部分。为降低涤纶绒类产品的碳排放,一方面可以采用低碳绿色原料或能源,另一方面改变加工方式和染色工艺。

Isothermal Crystallization Behavior of Poly (ethylene terephthalate)/Carbon Black Masterbatch

Poly(ethylene terephthalate) (PET)/carbon black (CB) masterbatch was prepared by melt blending using a separate feeding technique and its homogeneous dispersion morphology was confirmed by transmission electron microscope (TEM). The Avrami and Hoffman-Lauritzen secondary nucleation theories were employed to analyze the effect of high CB content on crystallization kinetics of PET, providing theoretical support for the development of masterbatch with high content of functional components. The Avrami exponents,average values of n,for PET and PET/CB masterbatch are both greater than 3, which indicates three-dimensional growth of crystals. In addition,no significant evidence for regime transition of PET is found applying Hoffman-Lauritzen secondary nucleation theory,though such observations have been reported previously in the literature. Furthermore,appropriate U* value for PET is determined to be 12 800 J/mol. For PET/CB masterbatch,a transition from regime I to regime II around 225℃ is observed with appropriate U* value (12 800 J/mol) . This phenomenon is consistent with a transition point in plot of G versus Tc . The fold surface free energy σe (100. 3 mJ/m 2) of PET is much greater than that of PET/CB masterbatch (48. 3 mJ/m 2) ,which indicates heterogeneous nucleation effect of CB particles.