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选用可控光源,分别用QE65000和NIRQuest512光谱仪,同时测得同一舌体在有光源和无光源两种条件下的漫反射光谱信息,并对光谱数据进行处 理.实验结果表明,在620~950 nm和1000~1150 nm之间舌体内部的组织结构对光谱的漫反射强度较大,获得的舌体光谱图比较光滑,能较好地去除环境杂散光的干扰,测得的漫反射光谱也能更好地反映舌体内部 组织成分,微循环状态等信息.为客观反映舌诊光谱信息提供了一种新的测试方法.

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羊肉是我国西北少数民族地区的主要肉类消费品,随着人们膳食结构的多样化和对羊肉营养价值认可度的不断提高,羊肉已从部分人消费转向全民消费.冷却羊肉与冷冻羊肉,热鲜羊肉相比成熟更加充分,营养价值更高,口感更好,已成为居民消费的主流.但由于我国冷链系统不够完善,冷却羊肉在加工,储藏,运输和销售中易发生变质,内部组分和外部感官性质都会发生变化.不同的包装方式肉的呼吸方式不同,内部组分和外部感官特性变化不同,对肉品货架期和品质变化规律影响也不同.pH,颜色亮度(L*)和微生物菌落总数与肉的新鲜度密切相关,三者是评价畜肉新鲜度的重要指标.

枣营养丰富,是新疆重要经济作物.鲜枣的分选有利于后续加工前剔除级别低的残次品,节省能量消耗减少成本.因此,本文以新疆阿克苏地区鲜骏枣为研究对象,使用近红外光谱技术,机器视觉技术,信息融合技术,开展了其重量等级分选,总糖预测,裂纹果分拣与鲜骏枣综合等级分选建模研究

Isolating, purifying, and identifying proteins in complex biological matrices are often difficult, time consuming, and unreliable. Herein we describe a rapid screening technique for proteins in biological matrices that combines selective protein isolation with direct surface enhanced Raman spectroscopy (SERS) detection. Magnetic core gold nanoparticles were synthesized, characterized, and subsequently functionalized with recombinant human erythropoietin (rHuEPO)-specific antibody. The functionalized nanoparticles were used to capture rHuEPO from horse blood plasma within 15 min. The selective binding between the protein and the functionalized nanoparticles was monitored by SERS. The purified protein was then released from the nanoparticles’ surface and directly spectroscopically identified on a commercial nanopillar SERS substrate. ELISA independently confirmed the SERS identification and quantified the released rHuEPO. Finally, the direct SERS detection of the extracted protein was successfully demonstrated for in-field screening by a handheld Raman spectrometer within 1 min sample measurement time.

To avoid introduction of milling media during ball-milling process and ensure uniform distribution of SiC and graphite in ZrB2 matrix, ultrafine ZrB2–SiC–C composite powders were in-situ synthesized using inorganic–organic hybrid precursors of Zr(OPr)4, Si(OC2H5)4, H3BO3, and excessive C6H14O6 as source of zirconium, silicon, boron, and carbon, respectively. To inhabit grain growth, the ZrB2–SiC–C composite powders were densified by spark plasma sintering (SPS) at 1950°C for 10 min with the heating rate of 100°C/min. The precursor powders were investigated by thermogravimetric analysis–differential scanning calorimetry and Fourier transform infrared spectroscopy. The ceramic powders were analyzed by X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. The lamellar substance was found and determined as graphite nanosheet by scanning electron microscopy, Raman spectrum, and X-ray diffraction. The SiC grains and graphite nanosheets distributed in ZrB2 matrix uniformly and the grain sizes of ZrB2 and SiC were about 5 lm and 2 lm, respectively. The carbon converted into graphite nanosheets under high temperature during the process of SPS. The presence of graphite nanosheets alters the load-displacement curves in the fracture process of ZrB2–SiC–G composite. A novel way was explored to prepare ZrB2–SiC–G composite by SPS of in-situ synthesized ZrB2–SiC–C composite powders.

We present low-cost bioenabled surface-enhanced Raman scattering (SERS) substrates that can be massively produced in sustainable and eco-friendly methods with significant commercial potentials for the detection of food contamination and drinking water pollution. The sensors are based on diatom frustules with integrated plasmonic nanoparticles. The ultra-high sensitivity of the SERS substrates comes from the coupling between the diatom frustules and Ag nanoparticles to achieve dramatically increased local optical field to enhance the light-matter interactions for SERS sensing. We successfully applied the bioenabled SERS substrates to detect melamine in milk and aromatic compounds in water with sensitivity down to 1μg/L.

Sol gel derived nanocrystalline yttria pellets are irradiated with 120 MeV Ag9+ ions for fluence in the range 1 1012–3 1013 ions cm 2. Pristine and irradiated samples are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and Raman spectroscopy. XRD pattern of pristine Y2O3 nanocrystal reveal cubic structure. A new XRD peak at 30.36 is observed in pellet irradiated with 1 1013 ions cm 2. The peak at 30.36 is corresponding to ?40 2? plane of monoclinic phase. The diffraction intensity of ?40 2? plane increases with Ag9+ ion fluence. Raman spectrum of pristine pellet show bands corresponding to cubic phase. And, ion irradiated sample show new peaks at 410, 514 and 641 cm 1 corresponding monoclinic phase. HR-TEM and SAED pattern of ion irradiated sample confirmed the presence of monoclinic phase. Hence, it is confirmed that, 120 MeV Ag9+ ions induce phase transformation in nanocrystalline Y2O3.

One of the fundamental aims of space mission is to understand the physical, chemical, and geologic processes and conditions of planetary formation and evolution. For this purpose, it is important to investigate analog material to correctly interpret the returned spacecraft data, including the spectral information from remote planetary surfaces. For example, mid-infrared spectroscopy provides detailed information on the mineralogical compositions of planetary surfaces via remote sensing. Data is affected by numerous factors such as grain size, illumination geometry, space weathering, and temperature. These features need to be systematically investigated on analog material in terrestrial laboratories in order to understand the mineralogy/composition of a planetary surface. In addition, Raman spectroscopy allows non-destructive analyses of planetary surfaces in the case of a landing mission.

In this paper, we report on a compact prototype capable both of lensfree imaging, Raman spectrometry and scattering microscopy from bacteria samples. This instrument allows high-throughput real-time characterization without the need of markers, making it potentially suitable to field label-free biomedical and environmental applications.

The responses of plant growth and secondary metabolites to light quality are useful measurements to determine suitable habitat conditions for the cultivation of medicinal plants. The effect of light quality (white, blue, yellow, and red light) on leaf growth, camptothecin yield, the enzymatic activity, and the expression of camptothecin biosynthesis-related genes were investigated in Camptotheca acuminata seedlings. This was accomplished via measuring total leaf biomass, camptothecin content, activities of TSB and TDC, and the relative expression of TSB, TDC1, and TDC2 genes. Compared with white light, the red light treatment displayed the highest leaf biomass, while yellow light and blue light inhibited the growth of the plants. The lowest leaf biomass was found in plants under the blue light treatment. On day 45, the highest values of CPT content were observed under blue light conditions, followed by yellow light, red light, and white light. Among the four light environments, camptothecin yield was the highest in plants grown under red light. Furthermore, activities of TSB and TDC as well as the relative expression of genes of TSB, TDC1, and TDC2 were significantly increased on day 45 under blue light as compared with the white light. This suggests that blue light up-regulated the expression of camptothecin biosynthesisrelated genes and induced camptothecin biosynthesis. The results indicate that red light was effective for inducing the production of camptothecin in C. acuminata seedling leaves. Manipulating light quality can be an effective means to achieve the highest camptothecin yield in medicinal plantation, but this conclusion needs to be further verified by more well-designed large-scale trials.

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