MICROSTRUCTURAL EVOLUTION OF HIGHLY UNDERCOOLED EUTECTIC Ni78.6Si21.4 ALLOY

A large undercooling level up to 550K （0.386Te） was achieved in eutectic Ni78.6Si21.4melt by the combination of molten-glass and cyclic superheating. A microcrystaUine structure is obtained at large undercooling. Surprisingly, the morphology of ct（Ni） phase transits from the non-faceted phaseto faceted phase at large undercooling of 390K. Based on the classical nucleation theory and transient nucleation theory, the process of microstructure evolution and competitive nucleation was analyzed, and the refinement of crystal structure is determined by the high nucleation rate under large undercooling.     

REACTIONS OF PYRITE IN CATALYTICAL OXIDATION ACID LEACHING SYSTEM

ＲＥＡＣＴＩＯＮＳＯＦＰＹＲＩＴＥＩＮＣＡＴＡＬＹＴＩＣＡＬＯＸＩＤＡＴＩＯＮＡＣＩＤＬＥＡＣＨＩＮＧＳＹＳＴＥＭ￥Ｘｉａ，Ｇｕａｎｇｘｉａｎｇ；Ｔｕ，Ｔａｏｚｈｉ；Ｙａｎｇ，Ｈａｎｌｉｎ；Ｓｈｉ，Ｗｅｉ（ＩｎｓｔｉｔｕｔｅｏｆＣｈｅｍｉｃａｌＭｅｔ...     

RELATIONSHIP OF THE PROPERTIES OF HOT－PRESSING C－BC_4－SiC COMPOSITE WITH THE CONTENT OF ADDITIVE Al

ＲＥＬＡＴＩＯＮＳＨＩＰＯＦＴＨＥＰＲＯＰＥＲＴＩＥＳＯＦＨＯＴ－ＰＲＥＳＳＩＮＧＣ－ＢＣ_４－ＳｉＣＣＯＭＰＯＳＩＴＥＷＩＴＨＴＨＥＣＯＮＴＥＮＴＯＦＡＤＤＩＴＩＶＥＡｌ￥Ｈｕａｎｇ，Ｑｉｚｈｏｎｇ；Ｔａｎ，Ｐｉｎｇ；Ｙａｎｇ，Ｑｉａｏｑｉｎ＋；Ｈ?..     

THERMODYNAMIC AND STRUCTURAL CHEMISTRY DISCUSSIONS FOR OXIDATIVE LEACHING OF Cu－Ni SULPHIDE ORE UNDER ATMOSPHERIC PRESSURE

ＴＨＥＲＭＯＤＹＮＡＭＩＣＡＮＤＳＴＲＵＣＴＵＲＡＬＣＨＥＭＩＳＴＲＹＤＩＳＣＵＳＳＩＯＮＳＦＯＲＯＸＩＤＡＴＩＶＥＬＥＡＣＨＩＮＧＯＦＣｕ－ＮｉＳＵＬＰＨＩＤＥＯＲＥＵＮＤＥＲＡＴＭＯＳＰＨＥＲＩＣＰＲＥＳＳＵＲＥ￥Ｗｕ，Ｗｅｎｊｉａｎ（Ｄｅｐａｒ...     

THICKENING TECHNIQUE OF CYCLONEFLOCCULATED SEDIMENTATION

ＴＨＩＣＫＥＮＩＮＧＴＥＣＨＮＩＱＵＥＯＦＣＹＣＬＯＮＥＦＬＯＣＣＵＬＡＴＥＤＳＥＤＩＭＥＮＴＡＴＩＯＮ￥Ｙａｎｇ，Ｘｉａｏｓｈｅｎｇ；ｃｈｅｎＪｉｎ；Ｌｕ，Ｇｕｉｚｈｉ；Ｃｈｅｎ，Ｔｉｎｇｚｈｏｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭｉｎｅｒａｌＥｎｇｉｎ...     

GRAIN REFINEMENT IN BULK UNDERCOOLED Ni-BASED ALLOY

Fluxing of 5 g bulk melt Ni77Si13B10 permits high undercoolings to be attained prior to nu-cleation onset.Investigations of grain refinement in the bulk undercooled alloy as a function ofundercooling,recalescence behavior and cooling rate have been reported.A significant inhomo-geneity of reduction in grain size of a bulk sample is observed,which is caused by the different so-lidification conditions:(1)recalescence process,and(2)the followed plateau in which the heatrelease and extraction rates are equal.It is concluded that the homogeneous refined microstructurecan be achieved if the initial undercooling prior to nucleation,or cooling rate after recalescence isfurther increased.     

Studying single nanocrystals under high pressure using an x-ray nanoprobe

In this report, we demonstrate the feasibility of applying a 250-nm focused x-ray beam to study a single crystalline NbSe(3) nanobelt under high-pressure conditions in a diamond anvil cell. With such a small probe, we not only resolved the distribution and morphology of each individual nanobelt in the x-ray fluorescence maps but also obtained the diffraction patterns from individual crystalline nanobelts with thicknesses of less than 50 nm. Single crystalline diffraction measurements on NbSe(3) nanobelts were performed at pressures up to 20 GPa.     

A case of Leukonychia with scanning electron microscope observation

Leukonychia is a medical term for white discoloration appearing on nails. The pathophysiologic mechanisms that cause white discoloration are not entirely clear. We processed a case of leukonychia with scanning electron microscope observation and found many crispy, obviously dissociated "layers" in the lower part of the white nail plate. The dissociated "layers" were composed of thick, loose, coarse keratin bundles intertwined with each other. We believe the dissociated "layers" are related to the clinically noted white discoloration appearing on the nails.     

Investigation of morphological and functional changes during neuronal differentiation of PC12 cells by combined hopping probe ion conductance microscopy and patch-clamp technique

PC12 cells derived from rat pheochromocytoma can differentiate into sympathetic-neuron-like cells in response to nerve growth factor (NGF). These cells have been proved to be a useful cell model to study neuronal differentiation. NGF induces rapid changes in membrane morphology, neurite outgrowth, and electrical excitability. However, the relationship between the 3D morphological changes of NGF-differentiated PC12 cells and their electrophysiological functions remains poorly understood.In this study, we combined a recently developed Hopping Probe Ion Conductance Microscopy (HPICM) with patch-clamp technique to investigate the high-resolution morphological changes and functional ion-channel development during the NGF-induced neuronal differentiation of PC12 cells. NGF enlarged TTX-sensitive sodium currents of PC12 cells, which associated with cell volume, membrane surface area, surface roughness of the membrane, and neurite outgrowth. These results demonstrate that the combination of HPICM and patch-clamp technique can provide detailed information of membrane microstructures and ion-channel functions during the differentiation of PC12 cells, and has the potential to become a powerful tool for neuronal research.     

Effect of enhanced coagulation by KMnO(4) on the fouling of ultrafiltration membranes

Pre-coagulation enhanced by KMnO(4) before ultrafiltration (KCUF) was compared with normal pre-coagulation by alum (CUF) in the ultrafiltration of water from the Songhua River, China. The trans-membrane pressure (TMP) with KCUF was much lower than that when alum alone was used. With KCUF a slower increment of TMP occurred, even under conditions of high river water turbidity. The results also showed that the removal of COD, UV(254) and TOC was appreciably higher after adding 0.5mg/L KMnO(4) compared with CUF. Although assimilable organic carbon (AOC) was increased by permanganate treatment, the AOC of the permeate from KCUF was nearly the same as that from CUF, showing that the cake layer on the surface of KCUF membrane could adsorb small molecules more effectively than that of CUF. This result was confirmed by the apparent molecular weight (MW) distribution measured by size exclusion chromatography (SEC). It was shown that flocs formed by KMnO(4) and alum were larger than those formed only by alum, causing higher removal of flocs and higher permeation flux. Lower NOM was found in the permeate from the KCUF systems because oxidation and adsorption of organic matter on the flocs occurred. The membrane was partly clogged by organic matter or other materials including some small flocs.