与大学生谈学物理

 物理学的发展已经历了三次大的突破,并导致了三次技术革命和工业革命,大大推动了人类社会的发展。十七、十八世纪,牛顿力学的建立和热力学的发展,推动了人类社会的发展.     

对自由电子激光（FEL）发展的评论

分析了自由电子激光的技术特性，评估了国内外的发展现状、趋势和应用前景，对发展自由电子激光的意义，它的地位、作用和难点进行了评论，对我国自由电子激光今后的发展提出了一些建议。     

光学玻璃的发展及其应用

随着光子学技术的发展，利用玻璃和光的相互作用改变光的极化态、频率、相干性和单色性，以及产生光子和探测光子的新型光功能玻璃成为光学玻璃发展的主要方向。本文针对光学玻璃及其在光学和信息技术等相关应用领域的重要性和发展作了介绍，重点阐述了非线性光学玻璃、梯度折射率光学玻璃、激光玻璃以及其他光功能玻璃的主要特性和发展状况，并对我国的光学玻璃工业发展作了回顾。     

现代机构精度分配理论的发展方向和关键

本文分析、探讨了机构精度分配理论和方法的组成和发展概况及其发展方向,在此基础上指出了发展现代机构精度分配理论问题的关键及其前景。     

大气痕量气体遥感探测仪发展现状和趋势

阐述了大气痕量气体探测技术的发展历程;详细介绍了几种国外先进的大气痕量气体遥感探测仪器的设计理念、工作原理和功能、工作模式、谱段设置和主要技术指标。讨论了我国遥感用星载大气痕量气体探测仪器的发展现状,给出了两种典型探测仪器的工作模式、谱段设置和主要性能指标。指出了未来星载大气痕量气体探测仪器的发展方向是提高遥感仪器的光谱分辨率、空间分辨率、灵敏度和定标精度以及发展主动遥感技术等,意在为我国今后这一领域的发展提供借鉴。     

国防光学计量技术的发展与展望北大核心CSCD

随着光学理论的发展和科技的进步,光学技术得到了迅速发展,对光学计量技术提出了新的要求和挑战。针对光学计量在国防军事中的重要性,分析了我国装备保障的发展对国防光学计量的新要求,介绍了国防科技工业光学一级计量站在光学成像和光辐射基础物理量计量、武器光电装备综合参数计量保障、光学前沿技术计量以及军用光电测试仪器研发方面的发展现状,提出了国防光学计量面临的主要问题及未来的发展方向。     

光子学的发展和光子产业

论述了光子学、光子技术的产生、发展和突破;阐明了光子学的定义、内涵、范畴和前沿;提出了关于第1类和第Ⅱ类光子产业的设想;予测了光子产业发展.     

干涉成像光谱仪技术的新发展

综述了成像光谱仪的发展过程以及空间调制干涉成像光谱仪技术的新原理、新技术、新发展。对干涉成像光谱技术的原理进行了论述 ,分析了Sagnac型和偏振型干涉成像光谱仪的分光机理和成像原理。提出了未来光谱仪技术的发展方向。     

空间太阳能电站发展及研究

随着国际能源危机的日益紧迫,空间太阳能电站（SPS）概念受到了世界各国的广泛关注,发展SPS,优化能源结构也成为我国解决能源需要的可靠途径。本文对SPS的起源、概念和发展历程进行了阐述,针对当前SPS典型系统模型,分析和总结了SPS的关键技术。结合我国当前的技术水平和未来科技发展的进步,对我国发展SPS提出了设想,采用先进的轻型薄膜聚光设计概念初步提出了一种新型SPS构型,并介绍了该构型的组成、功能及光路设计。该结构大大减小了系统质量,降低了运载的发射成本和发射难度,可为未来我国SPS的发展提供有益补充和借鉴。     

长余辉发光玻璃研究进展

介绍了长余辉发光玻璃的研究历程与进展，从长余辉发光玻璃的发展过程、发光机理、制备方法和发展现状等方面进行了分析，并对长余辉发光玻璃研究中存在的一些问题和发展方向提出了一些见解。     

Time domain finite volume method for the transient response and natural characteristics of structural-acoustic coupling in an enclosed cavity

A time domain finite volume method（TDFVM）based on wave theory is developed to analyze the transient response and natural characteristics of structural-acoustic coupling problems in an enclosed cavity.In the present method,the elastic dynamic equations and acoustic equation in heterogeneous medium are solved in solid domains and fluid domains respectively.The structural-acoustic coupling is implemented according to the continuity condition of the particle velocity along the normal direction and the normal traction equilibrium condition on the interface.Several numerical examples are presented to validate the effectiveness and accuracy of the present TDFVM.Then the effects of water depth on the acoustic and vibration characteristics and the natural characteristics of a structural-acoustic coupling system are analyzed.The numerical results show that the increase of water depth leads to a stronger coupling between the water and structure and the decrease of natural frequencies of coupling system,The computational cost and memory of this method are small and it can be applicable to structural-acoustic coupling problems in the heterogeneous fluid.     

Temperature Sensitivity Control and Mechanical Stress Effect of Boron-Doped Long-Period Fiber Gratings

We will present in this work the quantitative analysis of the relationship between the doping concentrations of GeO 2 and B 2 O 3 in the core and cladding regions and the temperature sensitivity of the resonance wavelength shift in long-period fiber gratings (LPFGs). Based on this analysis, the temperature sensitivity was suppressed and enhanced to 0.002 nm/°C and 0.28 nm/°C, respectively. We will also discuss the effect of the residual mechanical stress on the optical and mechanical properties of LPFGs. In particular, we will present the measurement results of the dependence of the refractive index change and mechanical strength on the residual mechanical stress in the boron-doped fibers with depressed clad and matched clad.     

2D-Mueller-matrix tomography of optically anisotropic polycrystalline networks of biological tissues histological sections

A new technique of Mueller-matrix mapping of the birefringent structure of biological preparations of human organs tissues is suggested. The algorithms of reconstruction of average values and magnitude of fluctuations of the phase (birefringence) and amplitude (dichroism) of optically anisotropic structure of myocardium and connective tissue component of the vaginal wall histological section are proposed. The magnitudes and ranges of changes in the statistical moments of the 1st-4th order that characterize the distribution of average values and magnitude of fluctuations of birefringence and dichroism of the myocardium and connective tissue of the vaginal tissues histological sections were determined. Joint studies of distributions of the characteristics of phase and amplitude of the anisotropy of myocardium and connective tissue component of the vaginal wall tissues of different states were performed. The cases of various necrotic changes in the myocardium and pathological conditions of the vagina wall (prolapse of the genitals) are examined. Balanced accuracy of the method of Mueller-matrix polarization-phase and diffuse tomography of optically anisotropic polycrystalline networks in the differentiation of necrotic and pathological changes in human organs is determined.     

不同比例有机无机肥配施土壤腐殖质组分的光谱学特征

以16年长期定位试验为基础,探讨不同比例有机无机肥配施对土壤腐殖质特征的影响。通过分离纯化腐殖质中的胡敏酸（HA）和富里酸（FA）组分,并利用元素分析、红外光谱和核磁共振研究分析了F1（70%化肥+30%有机肥）、F2（50%有机肥+50%化肥）和F3（100%有机肥）三种施肥方式下的HA和FA含量及结构变化。结果表明,F3对于提升HA和FA含量的效果优于F1和F2处理,说明有机肥的施用量越高,土壤腐殖质组分的含量就越高。元素分析表明,不同配比的有机无机肥对HA和FA各元素含量及原子比影响不同。F2和F3都提高了HA的缩合度,降低了氧化度和极性,其中F3的效果更加明显;有机肥的施用还能促进HA中含氮化合物的形成,并且在F2中的效果最好;有机肥的施用同样提高了FA的缩合度而降低了氧化度和极性并促进了含氮化合物的形成,尤其在F2处理中尤为明显。腐殖质红外光谱分析表明,与F1相比,F2和F3提高了HA中脂肪族化合物、碳水化合物物质的含量,FA的羧基基团、脂肪基团含量也增加,且在F3处理中表现最为显著;F2处理则降低了HA中脂肪烃物质的含量,FA中的碳水化合物则达到最高。13C核磁共振波谱分析显示,在三种处理中,有机肥的施用提高了HA和FA的脂化度而降低其芳化度,其中F2处理中HA官能团变化更加显著,FA在F3处理中则变化更加明显。综上所述,有机肥显著提高了土壤腐殖质组分含量,并且提高了HA和FA的脂化度降低其芳化度,但是不同用量有机肥下HA和FA的形成机制不同。     

Sono-electrolysis performance based on indirect continuous sonication and membraneless alkaline electrolysis: Experiment,modelling and analysis

In the present study, experiments of membraneless alkaline sono-electrolysis are combined to a mathematical model describing the performance of a sono-electrolyzer based on the electrochemical resistances and overpotentials (activation, Ohmic and concentration) and the oscillation of the acoustic cavitation bubble, and its related sono-physical and sonochemical effects, as a single unit and within population. The study aims to elucidate the mechanism of action of acoustic cavitation when coupled to alkaline electrolysis, using a membraneless H-cell configuration and indirect continuous sonication (40 kHz, 60 W_e). The calorimetric characterization constituted the bridge between experimental results and the numerical and simulation approach, while the quantification of the rate of produced hydrogen both experimentally and numerically highlighted the absence of the contribution of sonochemistry, and explained the role of ultrasounds by the action of shockwaves and microjets. Finally, the energetic sono-physical approach allowed an estimation of the predominance of the shockwaves and microjets effects according to the bubble size distribution within the population corresponding to the acoustic conditions of the study. The resulting macroscopic effect in sono-electrolysis process has been assessed considering the induced degassing. A reduction in the fraction of electrodes’ coverage by bubbles from 76% to 42% has been recorded, corresponding to a decrease of 7.2% in Ohmic resistance and 62.35% in bubble resistance.     

Spectroscopic and nano-molecular modeling investigation on the binary and ternary bindings of colchicine and lomefloxacin to Human serum albumin with the viewpoint of multi-drug therapy

Combination of several drugs is often necessary especially during long-term therapy. The competitive binding drugs can cause a decrease in the amount of drug bound to protein and increase the biological active fraction of the drug. The aim of this study is to analyze the interactions of Lomefloxacin (LMF) and Colchicine (COL) with human serum albumin (HSA) and to evaluate the mechanism of simultaneous binding of LMF and COL to protein. Fluorescence analysis was used to estimate the effect of drugs on the protein fluorescence and to define the binding and quenching properties of drugs-HSA complexes. The binding sites for LMF and COL were identified in tertiary structure of HSA with the use of spectrofluorescence analysis. The analysis of fluorescence quenching of HSA in the binary and ternary systems show that LMF does not affect the complex formed between COL and HSA. On the contrary, COL decreases the interaction between LMF and HSA. The results of synchronous fluorescence, resonance light scattering and circular dichroism spectra of binary and ternary systems show that binding of LMF and COL to HSA can induce micro-environmental and conformational changes in HSA. The simultaneous presence of LMF and COL in binding to HSA should be taken into account in the multi-drug therapy, and necessity of using a monitoring therapy owning to the possible increase of the uncontrolled toxic effects. Molecular modeling of the possible binding sites of LMF and COL in binary and ternary systems to HSA confirms the spectroscopic results.     

景德镇仿龙泉青瓷与龙泉青瓷组成特征研究

龙泉青瓷不仅受到了国内外陶瓷爱好者的热捧,还被不同地区广大窑工争相效仿,其中以景德镇明清时期仿制最具代表性。利用能量色散X荧光光谱分析仪对38 件宋、元、明时期的龙泉青瓷以及明代景德镇仿龙泉青瓷进行了测试,并结合烧成温度分析结果,从时空角度对比分析了两地青瓷胎釉组成特征、演变规律和形成原因,有助于了解我国南方青釉瓷的演变发展、相互交流和影响,为不同产地青瓷的断源断代提供了一定的科学依据。     

基于高光谱技术的酸奶中常见致病菌的快速鉴别及计数

酸奶是一种发酵型乳制品饮料,因其特殊的功能性和良好的口感而广受欢迎。但由于商业链的不正当运行,如奶源非法获取、灭菌不充分等原因,导致酸奶中致病菌大量滋生,酸奶中毒事件频繁发生。酸奶中常见的致病菌主要有大肠杆菌、金黄色葡萄球菌和沙门氏菌,这三种致病菌由人体摄入并达到一定的数量时会产生腹痛、腹泻等严重的消化道疾病,并且会破坏人体肠道内的正常菌群平衡,因此国标对奶制品中这三种致病菌的数量已有明确的限量规定。由于酸奶的主要消费对象为老人和小孩,故其潜在危害不容小觑。传统菌落检测方法虽具有简单,灵敏、可操作性强等优点,但当不同菌落混杂在一起时无法同时进行定性定量的检测,且具有试剂成本高,检测周期长,人为因素影响较大等缺点。因此开发一种快速、简单、准确的混合鉴定计数方法为避免致病菌对酸奶的潜在危害提供了有效的途径。高光谱技术同时包含样本的光谱信息与图像信息,既能够根据化学组分的微小变化进行精确识别（光谱信息）,又能够反映出菌株在外部多层次的变化（图像信息）。因此该研究尝试对比高光谱图像技术和光谱技术,采用模式识别的方法,对比不同的模型识别结果,优选出最佳识别率的识别模型作为计数模型,最后通过最佳鉴别计数模型的识别分类结果来达到对酸奶中常见致病菌鉴定计数的目的。首先,购买酸奶中常见的乳酸菌种（保加利亚乳杆菌、嗜热链球菌、嗜酸乳杆菌、干酪乳杆菌、植物乳杆菌）和潜在污染的致病菌种（金黄色葡萄球菌、大肠杆菌、沙门氏菌）等标准菌株进行培养,提取经过48 h培养后的菌落图像信息和光谱信息。采用几种不同的预处理方式（SNV,MC,MSC,1stDER,2ndDER）对所提取的光谱数据进行预处理,并应用遗传算法筛除光谱数据中冗余的波段,保留有效波段。利用图像处理技术对图像信息中的菌株与培养基背景进行去除,然后采用主成分分析法从每幅图中优选出3个特征波长,并运用图像处理技术从特征波长所对应图像中提取菌株的18个基于GLCM的纹理特征信息。挑选合适的主成分分别建立不同的鉴别模型（LDA,KNN,BP-ANN,LS-SVM）,通过其最终的鉴别模型的识别率来确定最佳鉴别计数模型。最后从标准菌株中分别挑选出30株进行计数测试,通过比较模式识别的分类数量结果与菌株的实际数量来验证模式识别效果的准确率。研究表明,运用SNV预处理后光谱数据在提高信噪比效果上明显优于其他几种预处理方式。745.790 8,773.098 4和779.207 0 nm为图像信息中方差贡献率最大的三个波长,运用从特征波长所对应的图像中所提取的纹理特征信息建立图像识别模型。通过对比图像信息和光谱信息的模式识别结果发现,光谱特征鉴别模型普遍优于图像纹理特征鉴别模型,且当主成分数为9时,运用光谱特征所建立的LS-SVM模型的校正集识别率为96.25%,预测集的识别率为91.88%,为最优模型。采用优选的最优模型对菌株进行识别计数,大肠杆菌计数的相对误差为3.33%,金黄色葡萄球菌和沙门氏菌计数的相对误差均为0,验证了高光谱技术应用于酸奶中常见致病菌的鉴别计数的可行性。     

Influences of Quantum and Disorder Effects on Solitons Excited in Protein Molecules in Improved Model

Utilizing the improved model with quasi-coherent two-quantum state and new Hamiltonian containing an additional interaction term [Phys. Rev. E62 (2000) 6989 and Euro. Phys. J. B19 (2001) 297] we study numerically the influences of the quantum and disorder effects including distortion of the sequences of masses of amino acid molecules and fluctuations of force constant of molecular chains, and of exciton-phonon coupled constants and of the dipole-dipole interaction constant and of the ground state energy on the properties of the solitons transported the bio-energy in the protein molecules by Runge-Kutta method. The results obtained show that the new soliton is robust against these structure disorders, especially for stronger disorders in the sequence of masses spring constants and coupling constants, except for quite larger fluctuations of the ground state energy and dipole-dipole interaction constant. This means that the new soliton in the improved model is very stable in normal cases and is possibly a carrier of bio-energy transport in the protein molecules.     

地塞米松磷酸钠和倍他米松磷酸钠两种差向异构体的FTIR,FT-Raman和SERS光谱研究

检测了地塞米松磷酸钠和倍他米松磷酸钠两种差向异构体的红外光谱(FTIR), 固体和饱和溶液的常规拉曼光谱(NRS)及以银胶为基底的表面增强拉曼光谱(SERS)。通过红外和拉曼光谱的结合,对其各基团的振动模式进行解析,并对峰进行归属和比较。结果表明：两种物质的主要区别是地塞米松磷酸钠的CH₃非对称伸缩振动和对称面内变形振动的拉曼位移较大;依据SERS作用机理和规律,推测两种物质在银胶上主要是通过P—O键、羧基和五元环与银胶垂直吸附。建立了两种差向异构体基于银纳米粒子的吸附模式,实现了对两种物质进行快速鉴别与区分的方法,为进一步研究肾上腺皮质激素类药物提供了十分重要的信息和可靠的参考。