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CsLiB6O10 (CLBO) is a high-performance nonlinear optical crystal, particularly suitable for high-power ultraviolet laser by fourth harmonic generation (FHG, 266 nm) and fifth harmonic generation (FIHG, 210 nm). A CLBO crystal with the size of 120 mm x 112 mm x 62 mm was successfully grown using top seeded solution growth (TSSG) method in this work. The grown CLBO crystal exhibits a complete appearance without macroscopic defects such as cracking and visible scattering particles. A CLBO FIHG crystal component was cut from this crystal, and its UV-visible-near infrared transmittance, optical uniformity and weak absorption properties were analyzed in detail. The results include that, the mean transmittance exceeds 90% from 210 nm to 1 800 nm, optical uniformity result is 3.8 x 10-5 and the weak absorption is 90 x 10-6cm-1 at 1 064 nm. All of these results indicate that the as-grown CLBO crystal possesses good transmittance in the ultraviolet region, high optical uniformity and low weak absorption, laying the foundation for subsequent research on related applications. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Donghua University (Natural Science Edition) is the property of Journal of Donghua University (Natural Science) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, 193 nm ultraviolet photodissociation-mass spectrometry (UVPD-MS) was applied to investigate supercharging reagent sulfolane in protein sequence and structure characterization. All datasets were collected by using an Orbitrap MS system equipped with an ArF 193 nm EX50 excimer Laser. The 193 nm UV laser has the advantages of high brightness, good stability, and propagate in air, which can directly excite and dissociate the protein backbone within 5 ns (single pulse). Previous reports demonstrated that the partial protein high-order structures and non-covalent interactions could be retained in the UVPD fragments and the site-specific fragmentation yields (FYs) revealed the dynamic protein structure alterations under different conditions. Therefore, the combination of UVPD with nMS provides a new research paradigm for the characterization of protein structure changes. In this work, we further demonstrated 193 nm UVPD was superior to high-energy collision induced dissociation (HCD) in fragmenting and sequencing the non-denatured carbonic anhydrase II (CA) generated in native electrospray ionization (ESI). UVPD could efficiently activate and fragmentate the non-denatured CA with different charge states in just 5 ns, achieving cleavage sequence coverage 79.8% for CA Z10. Then, 0.25% supercharging reagent sulfolane was added into the protein solution and the CA charge distribution was significantly moved to higher charge states under identical native ESI conditions. However, higher-order structures (HOS) and non-covalent interactions could be obtained as the CA charge distribution was still concentrated and significantly different from the spectra features of denatured CA. The UVPD cleavage sequence coverage of the CA was increased to 87.2%, including the regions that were difficult to be dissociated and characterized without sulfolane addition. In addition, the non-covalent of CA and Zn2+ remained stable, indicating that the addition of sulfoxide had little influence on the Zn2+ binding region. The UVPD sequence coverage of CA Z11 was increased by 7.4% after the addition of sulfoxide, but the site FYs were almost not changed, demonstrating the corresponding local structures were nearly not changed. However, the higher charge states introduced by sulfolane also exhibited the risk of inducing specific structure alteration of part of protein regions. In conclusion, it was infered that supercharging reagent is efficient in modulating the charge state distribution of proteins in native ESI-MS characterization and can expand the MS detection mass range. The introduction of supercharging reagent can further improve the UVPD sequence coverage, including the structure-compact regions hard to be fragmented. Although part of the protein HOS and non-covalent interactions seems retained, the influence of higher charge states on protein structures should be considered in dynamic protein structure investigation. [ABSTRACT FROM AUTHOR]

Ultraviolet nonlinear optical (NLO) crystals are the key materials to realize the development of ultraviolet solid-state lasers. At present, NLO crystals mainly rely on borate crystals, but the existing NLO crystals could not meet the applications fully. While it is increasingly difficult to find new NLO crystals, so it is particularly urgent to develop new material systems. From the relationship between borate structures and optical and nonlinear optical properties, it can be known that borates which containing planar conjugated groups have the characteristics of large frequency doubling coefficient, suitable birefringence and short UV cut-off edge. Group with planar conjugated configuration is the core functional unit of borate NLO crystals. The study of expanding planar conjugated groups based on geometric configuration is an important idea for exploring new systems of UV nonlinear optical materials. Based on these, our team proposes to expand the exploration scope of UV NLO crystals by studying CO3, NO3, C(NH2)3 groups with planar triangular conjugated structures and HC3N3O3, H2C4N2O3 groups with planar six-member ring conjuated structures. The research results obtained by our team in the exploration of UV crystals of carbonate, nitrate, guanidine, cyanurate and barbiturate in recent years are mainly introduced in this paper. [ABSTRACT FROM AUTHOR]

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Chemical vapor deposition ( CVD) technology has enabled synthetic diamonds to be applied in many fields, in which the excellent comprehensiveness of diamond has been fully developed, and may lead to a leap-forward development. The color center makes the diamond quantum accelerator initially show the feasibility of great power. Various scenarios, including the application of UV laser writing technology windows, maximize the comprehensive advantages of diamond windows in terms of optics, electricity, heat and mechanics. Ultra-wide bandgap diamond semiconductor applications will soon be realized, and diamond heat dissipation applications are constantly expanding. By summarizing the preparation methods and characteristics of CVD diamond, according to the intrinsic characteristics of diamond, CVD diamond is classified into quantum grade, electronic grade, optical grade, thermal grade and mechanical grade. The current status of research and application of CVD diamond are reviewed in detail, which is of great significance for judging the future development trend of CVD diamond. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A rapid method for the screening of hazardous chemicals in textiles was developed using antireflection-laser desorption ionization mass spectrometry (AR-LDI-MS). An antireflection material was used to replace the small-molecule matrix used in traditional matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). This material has quasi-periodical array structure on its surface, which is fabricated using one-step direct writing with ultrafast laser on a stainless steel plate. Light can be trapped after multiple reflections inside the structure, accompanied by the excitation of surface plasmon resonance, which converts light energy to heat. With over 90% UV laser energy converted to heat, this material allows thermal desorption and ionization of target analyte on the surface. Since no matrix is used, no interference at low m/z area is found in AR-LDI-MS analysis, which allows the detection of analytes of low molecular weights. The antireflection material is also durable and reusable after careful cleaning. In the screening process, the analytes were extracted and transferred to the antireflection surface, followed by LDI-MS analysis. The pulsed UV laser had a pulse frequency of 1 kHz and a wavelength of 355 nm, which provided the energy for sample molecules’ desorption and ionization. A high voltage of 2 500 V was applied between the antireflection material and the mass spectrometer capillary to guide the ions into the mass spectrometer. The whole process could be completed in less than 1 min, avoiding time-consuming sample pretreatment and excessive solvent consumption compared with traditional chromatography or chromatography-mass spectrometry methods. Six hazardous chemicals in textiles were analyzed including phthalate esters, caprolactam, diethanolamine and triethanolamine. The limits of detection (LODs) of phthalate esters (1 mg/kg) and caprolactam (1 mg/kg) were comparable with traditional methods, but the LODs of diethanolamine (60 mg/kg) and triethanolamine (50 mg/kg) were relatively high. Quantitative analysis of phthalate esters was also performed using internal standards. Six textile samples purchased from local supermarket and internet were used for the screening of hazardous chemicals mentioned before by the method, and only caprolactam was detected in one sample. AR-LDI-MS is suitable for the rapid and high-throughput screening of textiles, and it can be also potentially used for the screening of other consumer goods, like food, cosmetics and detergents. Detection of chemical residues on the human skin or object surface may also be a possible application. [ABSTRACT FROM AUTHOR]

The method of photodissociation spectroscopy based on mass spectrometry was rapidly developed and widely applied in gas phase ionic chemistry and analytical chemistry due to its high sensitivity and feasibility in recent years. In this research, an optical system with ultra-wide-band tunable laser output was constructed and combined with a 7.0 T Fourier transfer ion cyclotron resonance mass spectrometer (FT ICR MS). The system could be used to acquire “Action” spectra of isolated ions. Compared with the traditional absorption spectroscopy, it had the advantage of high sensitivity, which could completely eliminate influence of impurities and solvents. After its generation, the target ion could be selected in FT ICR cell, and irradiated by laser with different wavelengths. The energy obtained after absorbing photons at appropriate wavelengths could cause the ions to dissociate and to form fragment ions to be detected. By gradually changing the wavelength of laser and analyzing the mass spectra under different wavelengths, the photodissociation spectra of target ions could be obtained through data analysis. The system applied here could be used to obtain ultra-wide-band photodissociation spectra of different ions in the gas phase. The full spectral tunable range of the system was 192-3 700 nm, which was, as far as we knew, the widest available tunable spectral range fulfilled on a single mass spectrometer. The ultra wide wavelength coverage was realized by two wavelength tunable OPO lasers. The optical path was set in vacuum, which improved the transmission efficiency of lasers in ultraviolet and infrared regions. The system combined the advantages of electrospray ionization (ESI), high mass resolution and superior ion handling capability of FT ICR MS. The UV-visible and mid-infrared photodissociation spectra of the target ion could be obtained, which were complementary, corresponding to their electronic and vibrational energy levels of molecules, respectively. Since the full spectrum for some target ion was generated under the same ion source, it avoided some unexpected spectral differences caused by ionization conditions and other instrument-relative factors. In this paper, rhodamine 110 and tryptamine were taken as examples. Photodissociation spectra of corresponding ions in different wavelength range were obtained, which preliminarily proved the feasibility of the method. [ABSTRACT FROM AUTHOR]