Nucleation and crystallization of tailing-based glass-ceramics by microwave heating

The effect of microwave radiation on the nucleation and crystallization of tailing-based glass-ceramics was investigated using a 2.45 GHz multimode microwave cavity. Tailing-based glass samples were prepared fi＇om Shandong gold tailings and Guyang iron tailings utilizing a conventional glass melting technique. For comparison, the tailing-based glass samples were crystallized using two different heat-treatment methods： conventional heating and hybrid microwave heating. The nucleation and crystallization temperatures were determined by performing a differential thermal analysis of the quenched tailing-based glass. The prepared glass-ceramic samples were further characterized by Fourier transform infrared spectroscopy, X-ray diffraction, Raman spectroscopy, thermal expansion coefficient measurements, and scanning electron microscopy. The results demonstrated that hybrid microwave heating could be successfully used to crystallize the tailing-based glass, reduce the processing time, and decrease the crystallization temperature. Furthermore, the results indicated that the nucleation and crystallization mechanism of the hybrid microwave heating process slightly differs fi＇om that of the conventional heating process.

Hydriding and dehydriding kinetics of melt spun nanocrystalline Mg20Ni10-xCux (x = 0-4) alloys

The nanocrystalline Mg2Ni-type electrode alloys with nominal compositions of Mg20Ni10-xCux (x = 0, 1, 2, 3, 4) were synthesized by melt-spinning technique. The microstructures of the alloys were characterized by XRD, SEM and HRTEM. The hydrogen absorption and desorption kinet-ics of the alloys were measured using an auto-matically controlled Sieverts apparatus. The re- sults show that all the as-spun alloys hold ty- pical nanocrystalline structure. The substitution of Cu for Ni does not change the major phase Mg2Ni but it leads to the formation of the sec-ondary phase Mg2Cu. The hydrogen absorption capacity of the alloys first increases and then decreases with rising Cu content, but the hy-drogen desorption capacity of the alloys mono- tonously grows with increasing Cu content. The melt spinning significantly improves the hydro- genation and dehydrogenation capacities and kinetics of the alloys.

Exome sequencing analysis identifies novel homozygous mutation in ABCA4 in a Chinese family with Stargardt disease

AIM: To identify the disease-associated mutations in a Chinese Stargardt disease(STGD) family, extend the existing spectrum of disease-causing mutations and further define the genotype-phenotype correlations.METHODS: A Chinese STGD family and 200 normal controls were collected. Whole exome sequencing(WES) and bioinformatics analysis were performed to find the pathogenic gene mutation. Physico-chemical parameters of mutant and wildtype proteins were computed by Prot Param tool. Domains analysis was performed by SMART online software. HOPE online software was used to analyze the structural effects of mutation. Immunofluorescence, quantitative real-time polymerase chain reaction and Western blotting were used for expression analysis.RESULTS: Using WES, a novel homozygous mutation(NM_000350: c.G3190 C, p.G1064 R) in ABCA4 gene was identified. This mutation showed co-segregation with phenotype in this family. It was not found in the 200 unrelated health controls and absent from any databases. It was considered "Deleterious" as predicted by five function prediction softwares, and was highly conserved during evolution. ABCA4 was expressed highly in the human eye and mouse retina. The p.G1064 R was located in AAA domain, may force the local backbone into an incorrect conformation, disturb the local structure, and reduce the activity of ATPase resulting in the disease pathology. CONCLUSION: We define a novel pathogenic mutation(c.G3190 C of ABCA4) of STGD. This extends the existing spectrum of disease-causing mutations and further defines the genotype-phenotype correlations.

Novel KDM6A mutation in a Chinese infant with Kabuki syndrome: A case report

BACKGROUND Kabuki syndrome(KS)is a rare syndrome characterized by multisystem congenital anomalies and developmental disorder.KMT2D and KDM6A mutations were identified as the main causative genes in KS patients.There are few case reports and genetic analyses,especially of KDM6A gene mutation,in China.CASE SUMMARY This study reports a de novo KDM6A mutation in a Chinese infant with KS.A 2-month-old Chinese baby was diagnosed with KS,which manifested as hypoglycemia,congenital anal atresia at birth,feeding difficulties,hypotonia,and serious postnatal growth retardation.He died of recurrent respiratory infections at age 13 mo.DNA sequencing of his blood DNA revealed a novel KDM6A frameshift mutation(c.704_705delAG,p.N236Sfs*26)(GRCh37/hg19).CONCLUSION We present a Chinese KS patient with a novel KDM6A frameshift mutation(c.704_705delAG,p.N236Sfs*26)(GRCh37/hg19),broadening the mutation spectrum.

Microstructure and mechanical properties of lightweight AlCrTiV_(0.5)Cu_(x) high-entropy alloys

High-entropy alloys(HEAs)are an emerging and rapidly developing family of alloys with appealing properties such as lightweight HEAs with excellent mechanical properties.In this study,to obtain lightweight HEAs with exceptional hardness,we prepared AlCrTiV_(0.5)Cu_(x)(x=0,0.2,0.4,0.6,0.8 and 1.0,denoted as Cu_(0),Cu_(0.2),Cu_(0.4),Cu_(0.6),Cu_(0.8) and Cu_(1.0) alloys,respectively)HEAs and analyzed their microstructure and hardness.

Structure and electrochemical performances of Mg20-xYxNi10（x=0-4） alloys prepared by mechanical milling

Mg2Ni-type Mg20-xYxNi10(x=0,1,2,3 and4) electrode alloys were fabricated by vacuum induction melting.Subsequently,the as-cast alloys were mechanically milled on a planetary-type ball mill.The effects of milling time and Y content on the microstructures and electrochemical performances of the alloys were investigated in detail.The results show that nanocrystalline and amorphous structure can be successfully obtained through mechanical milling.The substitution of Y for Mg facilitates the glass forming of the Mg2Ni-type alloy and significantly enhances the electrochemical characteristics of the alloy electrodes.Moreover,the discharge capacity of Y-free alloy monotonously grows with the milling time prolonging,while that of the Y-substituted alloys has the maximum values in the same case.The milling time of obtaining the greatest discharge capacity markedly decreases with Y content increasing.The electrochemical kinetics of the alloys,including high rate discharge ability(HRD),diffusion coefficient(D),limiting current density(IL) and charge transfer rate,monotonously increase with milling time extending.