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In this paper, colorless and transparent Ce3 + activated borogermanate scintillating glass was prepared in air atmosphere by traditional melt-quenching method. The total content of GeO2 and Gd2 O3 in the borogermanate scintillating glass is 85%, and the measured density is about 5. 82 g/cm3. The linear transmittance of the glass scintillator is more than 80% in the wavelength range of 450 nm to 800 nm. A small amount of tartaric acid (C4 H6 O6) was added as a strong reducing agent to reduce the production of Ce4 +. The fluorescence decay characteristics of Ce3 + in the borogermanate scintillating glass at 340 nm excitation wavelength were studied under different dosage of tartric acid, and the optimal dosage of tartric acid was also determined. In addition, the light yield of borogermanate scintillating glass was rarely reported before. In this work, the light yield of the prepared Ce3 + activated borogermanate scintillating glass is measured as 27 ph/MeV, and the high density Ce3 + activated borogermanate scintillating glass has a minimum decay time of about 14. 40 ns. It can be predicted that the prepared borogermanate scintillation glass with high density and fast decay time has great development potential in the fields of high energy physics and medicine imaging. [ABSTRACT FROM AUTHOR]

BACKGROUND: Knowledge of the chemical composition of whole-rock geological samples is the basic work of geochemical research. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) has become the most powerful tools of elemental analysis as its advantages of direct solid sampling, avoiding the cumbersome wet chemical digestion process of traditional analytical techniques, low-pollution and low-consumption and high-efficiency. However, the small sample volume of laser ablation cannot represent the chemical composition of complex and inhomogeneous samples, resulting in poor analytical precision and accuracy, which hinders its application in whole-rock bulk analysis. It is critical to prepare complex whole-rock geological samples into homogeneous and stable sample targets. OBJECTIVES: To establish a green and efficient pretreatment technique for LA-ICP-MS whole rock analysis of complex geological samples. METHODS: The samples were first calcined at 1000-1100℃ to remove volatiles, pressed into pellets, and then melted by high-energy wide pulse width infrared laser irradiation to finally obtain a homogeneous and stable sample glass. RESULTS: Compared with pressed powder pellets, the new sample preparation procurement improved the analytical precision of each element in marine sediments GBW07354 and GBW07356 by an average of 7.7 times and 3.9 times, respectively. The deviation between the measured values and reference values of most elements in marine sediment samples was within 10%; the deviation between the measured values and reference values of most major elements, REEs, and other trace elements in soil composition standards was within 5%, 20%, and 15%, respectively; the number of elements measured in bauxite samples reached 40, and the compositions of Sc and W elements were given for the first time. CONCLUSIONS: Rapid and accurate analysis of major and trace elements in marine sediment, soil, and bauxite standard samples has been determined through the optimized pretreatment technique. The sample preparation procurement established in this paper allows the LA-ICP-MS technique to be directly and better applied to the elemental analysis of complex geological whole rock samples, further improving the efficiency of major and trace element analysis in geological samples. [ABSTRACT FROM AUTHOR]

For the problem of image degradation caused by raindrops attached to the lens or glass surface, this paper proposed a multi-stage progressive image raindrop removal method which divides the raindrop removal process into multiple stages to easily implement. First, the multi-scale fused encoder-decoder network at each stage designed to learn raindrop features. The constructed multi-scale dilated convolutions with gated recurrent units refined the internally transferred spatial features. In addition, the no dimensionality reduction channel attention module extracted channel information under specific spatial features. Finally, this paper adopted cross-stage feature fusion mechanism to strengthen the information exchange between the parts of each stage. Adding horizontal connections between the encoder-decoder networks in each stage to realize the horizontal transfer of feature information. And adding a supervised attention module to enhance the information transmission between different stages. The raindrop removal is progressively achieved. Experiments show that the proposed method can effectively remove raindrops. [ABSTRACT FROM AUTHOR]

Transparent ceramic is a kind of inorganic nonmetallic material with broad application prospects. However, the traditional preparation strategy based on powder sintering has technical limitations of relying on high-quality raw material powder, requiring long time high temperature treatment, complex equipment and process, and high production cost. Glass crystallization is a new method to achieve full crystallization of glass and obtain transparent ceramics by controlling the crystallization process. This method can overcome the technical difficulties associated with the traditional transparent ceramic processing. Meanwhile, it also shows unique advantages in preparing high density, pore-free, non-cubic phase, nanostructured transparent ceramics and has attracted significant attention. In this paper, the development and research status of glass crystallization method were reviewed in detail from two aspects: fully glass-crystallization of oxide transparent ceramics and related component systems. Then, the problems existing in the current research were pointed out, and the future development prospects were prospected. It is expected that this method can be widely used to prepare the next generation of high performance transparent ceramic materials. [ABSTRACT FROM AUTHOR]

Vitrification of municipal solid waste incineration (MSWI) fly ash is a promising technology to treat hazardous wastes・ The feed-to-glass conversion during the melting solidification process has been of great concern・ Phase transformations of fly ash and the feed (the mixture of fly ash and glass additive) at elevated temperature were analyzed w让h ICP-AES, IC, DSC and XRD・ The results show that the fly ash is mainly composed of Ca, Si, and Cl, and the crystalline phases mainly include hydrous compounds, chlorides, carbonates, and sulfates・ Fly ash occurs dehydration of hydroxides, decomposition o£ carbonates and formation of silicate intermediate phases as the temperatures increased・ After included glass additives (SiO2 and B2O3), the reactions of dehydration and decarbonation could hardly be affected, while the formation of intermediate silicate phases occurs in the lower temperature and the amorphous phase starts to appear in the feed at 850 ・ The feed finally turns to molten glass at 1300 °C ・ Additionally, prolonging the heat-treatment time could promote feed reactions. [ABSTRACT FROM AUTHOR]

The cryopreservation and transplantation of ovarian tissue is technically feasible, and the effectiveness is improved with the development of technology. It can be used to preserve female fertility, especially to preserve the fertility of prepubertal women with cancer who will have radiotherapy and chemotherapy. Vitrification is considered to be one of the most promising methods for cryopreservation of ovarian tissue, but its safety and efficacy need to be further verified. Cryogenic injury and transplantation ischemia-reperfusion injury are two problems of further development of cryopreservation and transplantation, in which the difficulty and focus are how to preserve follicles effectively. The existing freezing and transplantation conditions and effects are evaluated from six aspects of cryoprotectant, ovarian tissue size, cryocarrier, antioxidants, promoting angiogensis and hormones, in order to advance the project of female fertility preservation. [ABSTRACT FROM AUTHOR]

The grinding experiment of soda-lime glass was carried out to study the effects of grinding parameters on the surface roughness and morphology of the glass. The surface morphology was compared after grinded by different coated micro-grinding tools and surface roughness under different cooling conditions were also analyzed. The results show that when the grinding speed increases and the grinding depth and feed rate decrease, the surface roughness decreases and the surface morphology becomes smoother and better. Under different cooling conditions, the level of surface roughness after wet grinding is lower and the surface quality is better. In comparison with the CBN-coated micro-grinding with the same granularity, the diamond-coated micro-grinding can perform a better surface quality and more suitable for hard and brittle materials, such as glass. [ABSTRACT FROM AUTHOR]

BACKGROUND: Quantitative analysis of ancient glass and vitreous materials has important significance for studying its production time, origin, source of raw materials and production process. Compared with traditional analysis methods (eg. EPMA, EDX-SEM), LA-ICP-MS can be used to analyze the primary, minor and trace elements in samples quickly and accurately. OBJECTIVES: To investigate the composition of archaeological glass and discriminate its sources. METHODS: The element concentration in ancient glass and vitreous materials were determined by LA-ICP-MS. The surface morphologies of pits in glasses were displayed by AFM. RESULTS: The matrix effect among NIST610 and Corning A-D was insignificant under 193nm laser system and this experimental condition. A quantification strategy based on NIST610 and normalization to 100% (w/w) was suitable for analyzing Corning A-D and ancient glass samples. Study on different ablation modes in the experiment is helpful for the establishment of different experimental conditions to meet the requirement of different studies. CONCLUSIONS: Unearthed samples were analyzed, which provided data support for the source of the product. [ABSTRACT FROM AUTHOR]

According to the rule of mixture, glass-based composites containing β-eucryptite and mullite fibers were prepared by ball milling, cold isostatic pressing and high temperature vacuum sintering. The effects of fiber content, fiber length-diameter ratio and sintering temperature on the density, Vickers hardness and expansion coefficient of the composites were studied. The results show that composite exhibited high Vickers hardness value with a fiber content of 18wt%. Low expansion coefficient of 1.67×10-6/K (150-400 ℃) could be obtained when the content of fiber was 10wt%, ratio of length to diameter was 31, and the vacuum sintering temperature was 800 ℃ for 5 h. [ABSTRACT FROM AUTHOR]

Blast furnace slag modifying experiments using iron tailings were conducted to investigate the effect of acidity coefficient(Mk)on crystallization property， viscosity and surface tension of modified-blast-furnace-slag. The results indicated that crystallization temperature of modified slag significantly decreases with the increase of Mk and the slag system is still unordered glass phase with slag temperature decreasing to 1100℃ when Mk is above 1.4. The sensitivity of slag viscosity to temperature change gradually decreases， the temperature range corresponding to theoretically suitable fiber-formation-viscosity range of slag wool gradually increases， and the difference between minimum fiber-formation-temperature and crystallization temperature in suitable fiber-formation-viscosity range(Δt=(tw-tl))， which is only 101.7℃ when Mk is 1.2， gradually increase with the increase of Mk. The effect of Mk on surface tension of slag is small and the ratio of surface tension to viscosity， σ/η， symbolizing difficult degree of slag-forming， gradually decreases with the increase of Mk in suitable fiber-formation-temperature range. [ABSTRACT FROM AUTHOR]

Objective To analyze the diagnostic value of multi-slice spiral CT(MSCT) in cystic lung cancer. Methods MSCT of 29 patients with cystic lung cancer confirmed by pathology was retrospectively analyzed. The relationship between the location of the lesion and the cyst as well as the surrounding imaging features were analyzed. Results The tumors appeared as ground glass opacities with cystic cavities(8/29, 27.6%), 5 of which were ground glass nodules within the ground glass opacities.Other appearances included solid nodules with cystic cavities(15/29, 51.7%), mixed ground glass opacities and solid nodules with cystic cavities(6/29, 20.7%). The cysts were peripheral(26/29, 89.7%) or central(3/29, 10.3%). Follow-up showed enlarging solid components with increasing density(6/11), enlarging cysts with mural thickening(8/11) and cystic change in initially solid nodules(6/11). Conclusion Solid nodule with peripheral cystic cavity is a typical MSCT appearance of cystic lung cancer. Analyzing the imaging features of the main lesion and cyst with follow-up can aid imaging diagnosis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Bioactive glass is biocompatible, osteoconductive and osteoinductive. Therefore, bioactive glass has great potential in the treatment of bone defects. OBJECTIVE: To carry out a series of researches on the combination of bioactive glass and metal elements so as to maximize the development and utilization of bioactive glasses and to boost the development of local precision treatments. METHODS: By retrieval of WanFang, CNKI, PubMed databases, literatures on functional bioactive glass were obtained, in which studies addressing the further functional enhancement of bioactive glass in combination with metal ions were screened out. RESULTS AND CONCLUSION: Current bioactive glass can be combined with a variety of functional metal ions, thereby endowing it with antibacterial, pro-angiogenic, and magnetocaloric functions. Moreover, this review prospects the application of functional bioactive glass in orthopedics. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of bioglass and peptide /P-15 bone substitute material on the repair of rabbit cranial bone defect. Methods Bioglass was saturated with different concentrations of solution of the P-15 peptide（100， 200，400 μg/mL）and cultured with bone marrow stromal cells in vitro（the experimental group）. Bioglass without P-15 served as a negative control group. Then the alkaline phosphatase（ALP）activity of bone marrow stromal cells was detected at 1，3，7， 10d after inoculation to choose the composite materials with the optimum concentration of P-15 to implant into the cranial bone defect of rabbit（composite group）. The quality and quantity of new bone formation was observe by X-ray and histology staining at 4th，6th，8th week after implantation. Results At the concentration of 200μg/mL of the P-15 in phosphate buffered saline， the bone marrow stromal cells which were cultured with the Bioglass/P-15 showed greater alkaline phosphatase（ALP）activity than that at the concentrations of 100，400μg/mL in experimental group and the negative control group，and the difference had statistical significance（P<0.05）.The new bone formation of cranial bone defect of rabbit at 4th，6th，8th week in the composite group was better than that in the negative group. Conclusion Bioglass/P-15 bone substitute materials can accelerate the repair of rabbit cranial bone defect. [ABSTRACT FROM AUTHOR]

BACKGROUND: One-piece glass fiber post-and-core achieves a good sealing between cast-post and core and provides a suitable elastic modulus of the glass fiber material. Therefore, selecting a reasonable bonding system for the CAD/CAM-fabricated fiber post-and-core with no ferrule effect has become an important issue in clinical practice. OBJECTIVE: To compare the bonding effects of three kinds of adhesive materials without ferrule effect in the CAD/CAM-fabricated dental restoration after bypass obturation of oval root canals. METHODS: Ninety extracted first mandibular premolars with the working length set to 14 mm were randomized into three groups (n=30 per group). The root canal was prepared with the ProTaper next nickel titanium system under a dental operating microscope. The bypass obturation with oval root canals was achieved using the warm gutta-percha vertical condensation technique. 1-4 # Pesso drills were used to remove the gum in the root canal, with the preparatory depth of 9 mm, but with no shoulder collar. CAD/CAM technology was used to prepare one-piece fiber post-and-cores which were bonded using the KetacTM Cem Easymix glass ion, ONE-STEP PLUS universal UV-curable adhesive and RelyXTM Unicem 2 self-adhesive resin cement in different groups. The bonding effect of three kinds of adhesive materials was analyzed by using a universal mechanical measuring instrument. RESULTS AND CONCLUSION: Compared with the KetacTM Cem Easymix glass ion group, the debonding force and micro-tensile strength were significantly stronger in the other two groups (P < 0.05), while compared with the ONE-STEP PLUS universal UV-curable adhesive group, the debonding force and micro-tensile strength were slightly higher in the RelyXTM Unicem 2 self-adhesive resin cement group, but there was no significant difference between the two groups. To conclude, RelyXTM Unicem 2 self-adhesive resin cement in the absence of ferrule effect can achieve better bonding effect on the CAD/CAM-fabricated one-piece fiber post-and-core after bypass obturation of oval root canals.  [ABSTRACT FROM AUTHOR]