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Pellet-Cladding Interaction (PCI) is one of the most important issues in fuel rods of a Pressure Water Reactor (PWR) which may cause the failure of fuel rods, and it should be analyzed under operat...

Chromite is one of the earliest crystallized minerals from mafic melts and has been used as an important “petrogenetic indicator.” Its composition may be modified by interaction with intercumulate melt and adjacent minerals. Thus, chromite in mafic-ultramafic rocks contains clues to the geochemical affinity, evolution, and mantle source of its parent magmas. The Devonian Xiarihamu intrusion, located in the East Kunlun Orogenic Belt in the northern Tibet Plateau, China, hosts a very large disseminated Ni-Co sulfide deposit. This study focuses on geochemistry of the chromite enclosed in olivine of ultramafic rocks of the intrusion. Enrichments in Mg and Al in the rim of the chromite indicate only minor effects of alteration on the compositions of the chromite. The chromites enclosed in the olivines with forsterite percentage (Fo) lower than 87 are characterized by large variations in major and trace elements, such as large ranges of Cr·100/(Cr+Al) (Cr# = 15–47), Mg·100/(Mg+Fe2+) (Mg# = 41–65), and Al2O3 (= 26–53 wt%) as well as 380–3100 ppm V, 70–380 ppm Ga, and 1100–16300 ppm Zn. The chromites display positive correlations between Cr/(Cr+Al) and Ti, Mn, V, Ga, and Sc, inconsistent with fractional crystallization but indicative of an interaction between the chromites, intercumulate melts and hosting minerals. In contrast, chromites hosted in olivine with Fo > 87 in harzburgite have small variations in Cr# (ranging from 37 to 41), Mg# (48 to 51), and Al2O3 (30 to 35 wt%) as well as restricted variation in trace elements, indicating relatively weak interaction with trapped liquid and adjacent phases; these compositions are close to those of the most primitive, earliest crystallized chromites. The most primitive chromite has similarities with chromite in mid-ocean ridge basalt (MORB) in TiO2 and Al2O3 contents (0.19–0.32 and 27.9–36.3 wt%, respectively) and depletion of Sc and enrichment of Ga and Zn relative to MORB chromite. The geochemistry of the chromite indicates a partial melting of the asthenospheric mantle that was modified by melts derived from the subduction slab at garnet-stable pressures.

SnO2/AgIO4 hybrids were fabricated by an in-situ synthetic method at room temperature. The structure, morphology, light response range, separation efficiency of the electron-hole pairs and elements of the as-synthesized samples were characterized by adopting X-ray diffraction, scanning electron microscopy, UV-Vis diffuse reflectance spectroscopy, electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy, respectively. The synergistically photocatalytic degradation mechanism of the as-synthesized composites was also proposed. The experimental results reveal that under the visible light irradiation the as-synthesized SnO2/AgIO4 hybrids can enhance the photocatalytic degradation efficiency of rhodamine B compared to pure samples. With increasing the molar ratios of AgIO4 to SnO2, it displays the trend of first increasing and then decreasing. When it is 1:2 in 150 min, the as-prepared hybrids have the highest degradation efficiency of 93.1%, which increases by 6550.0%, 30.5%, and 1505.0% compared to those of pure SnO2, AgIO4, and TiO2 (P25), respectively. Moreover, the Sn-O-Ag cross-linking bonds are formed at the interfaces of SnO2 and AgIO4. In addition, superoxide anion radicals and holes play a major role in the process of photodegradation.

Rubi Fructus is a commonly used traditional Chinese medicine. The origin of Rubi Fructus is the dried fruit of Rubus chingii, a plant of the family Rosaceae, according to the 2015 edition of Chinese pharmacopoeia. There are some differences in the plant origin of Rubi Fructus in ancient herbal literature, to trace back its sources, we conducted a textual research on its origin, producing areas, quality evaluation, processing and concocting, properties, tastes and efficacy etc. based on the records of ancient herbal literatures and combined with plant morphology and related investigation. RESULTS:: showed that the variety of Rubi Fructus was more complex among ancient herbal literature, including R. coreanus, R. hirsutus, R. corchorifolius, R. foliolosus and other mixed varieties. Most scholars believe that the R. chingii has not been recorded in ancient herbal literature, while R. chingii was recorded as early as the Ming Dynasty in Compendium of materia medica through our textual research. Ancient Chinese herbs recorded that Rubi Fructus was mostly produced in Hubei, Shandong, Shanxi and Jiangsu provinces, while R. chingii mainly produced in Anhui, Jiangsu, Zhejiang, Jiangxi, Fujian and other provinces nowadays. Also, it was recorded that Rubi Fructus harvested in wheat field during May were the best. Besides, R. chingii with big, full, grain integrate, firm, yellow and green color, sour taste and impurity free possess the best quality in the contemporary. The ancient records of processing and concocting, properties, tastes and efficacy were basically the same as modern ones.These results provide the basis for the correct utilization and further development of Rubi Fructus.

Zn2SnO4/few-layer boron nitride nanosheets (FBNNS) hybrids were synthesized via a one-step hydrothermal method. The structures, morphology, optical properties, electron transformation and separation of the as-prepared products were characterized by X-ray diffraction, transmission electrical microscopy, UV-vis diffuse reflectance spectroscopy and electrochemical impedance spectroscopy, respectively. Rhodamine B was used to evaluate the photocatalytic activities of the as-prepared samples under visible light illumination. The photocatalytic mechanism was also explored. Experimental results showed that the degradation efficiency of rhodamine B was firstly increased and then decreased with increasing the usage amount of FBNNS. When it was 9 wt% based on the weight of Zn2SnO4, the degradation efficiency of the as-prepared Zn2SnO4/FBNNS-9 wt% composites reached to the maximum of 97.5% in 180 min, which was higher than 39.2 % of pure Zn2SnO4. Moreover, the holes played mainly active roles in photocatalytic reaction process. In addition, the as-prepared hybrids could enhance the separation efficiency of photoexcited carriers compared to pure Zn2SnO4.

The migration properties of uranium vacancies and interstitials in zirconium-doped uranium dioxide are studied by using density functional theory (DFT) and the climbing-image nudge elastic band (CI-NEB) method. The strong correlations among uranium 5f electrons were described by using a spherically averaged Hubbard parameter. In the model, the zirconium atoms are introduced by replacing the uranium atoms at the nearest and the next nearest neighbor sites along the diffusion path of uranium defects. The doping with zirconium obviously reduces the migration barriers for defects in uranium dioxide. The effect of doping with zirconium on the diffusion of uranium defects decreases with increasing distance between the zirconium dopant and the uranium defects. Further, we investigated the lattice distortion and the electron transfer associated with the migration of uranium defects, and we analyzed the physical origin of the reduction in the migration barriers caused by zirconium doping.

A novel AgCl/AgIO4 composite was fabricated via an in-suit synthetic method. The as-prepared samples have been characterised by using X-ray diffraction, transmission electron microscopy, scanning electron microscopy, UV–vis diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy and electrochemical impedance spectroscopy. Rhodamine B dilute solution was used to discuss the photocatalytic activities of the as-prepared composites under the visible light irradiation. Experimental results showed that with increasing the contents of AgIO4 the photocatalytic activity of the as-prepared hybrids was first increased and then decreased. When the molar ratio of AgCl to AgIO4 was 1:5, in 30 min, the as-prepared composites with the bandgap of 1.21 eV exhibited the highest photocatalytic activity and possessed 96.3% of degradation efficiency. That was increased by 71.5 and 27.9% compared with AgCl and AgIO4, respectively. Moreover, AgCl was linked with AgIO4 via chemical bonds rather than physical contact at the interfaces of these two semiconductors. In addition, a possible photocatalytic degradation mechanism for the as-prepared hybrids was also presented.

The nanosized Bi-doped SnO2/reduced graphene oxide 3D hybrids have been synthesized via one-step hydrothermal method. The structures, morphologies, photocatalytic activities of the as-prepared samples were discussed, respectively. The formation mechanism of the as-prepared hybrids was also proposed. Experimental results indicated that the usage amount of Bi2Sn2O7 obviously affected the photocatalytic performance of the as-prepared products. When it was 450 mg, the as-prepared sample possessed the band gap energy of 1.9 eV and the photocatalytic efficiency of 90% in 210 min for degradation of rhodamine B solution. In addition, triethylene tetramine and the as-prepared carbon hydrogel could act as reductant to synergistically reduce Bi2Sn2O7 into Bi-doped SnO2 particles during the formation of the hybrids.

Hexagonal boron nitride was adopted as a heterogeneous nucleation agent to fabricate polyamide 6 based nanocomposite films via a solution casting method. Isothermal crystallization behaviors of the...

This paper looks into the influences of martensitic transformations on the cavitation-erosion (CE) damage initiation mechanism and pitting corrosion resistance of a lean austenitic stainless steel. The ε and α' martensites are prime sites of CE damage initiation for this steel, whereas grain boundaries are more favourable damage initiation sites for other similar steels. The profusion of ε and α' results in fast surface roughening during the CE process, which may cause a compromise in performance when this steel (or similar steels that have the same CE damage mechanism) is used for such applications as hydro-machinery or piping. ε and α' also detrimentally affect the pitting resistance of this steel and so they are expected to affect CE resistance adversely due to the synergism between CE and corrosion.

The pellet cracking and relocation recovery is an important physical phenomenon for LWR fuel and also is an indispensable model for the fuel performance analysis code. During rise to power, there exists a large temperature gradient within the pellet from the centerline to the cooler periphery and it is enough to induce cracking to release the thermal stress. Simultaneously, the pellet diameter increases rapidly. Once the fuel rod gap is closed, the cladding constraint produced by pellet-cladding interaction plays an important role in the process of relocation recovery. In this paper, a new relocation recovery model as a function of power, contact pressure and time is established. The new model has been successfully implemented in the fuel rod performance analysis code JASMINE. Based on comparisons between code predictions and experimental measurements, the results indicate that the newly developed relocation recovery model has an excellent predictive ability.

The studies about surface production of hydrogen negative ions play an important role in many technologies. In the present paper, a low energy molecular hydrogen ion beam was irradiated to the porous Ni sheet. It was found that negative atomic hydrogen ions were detected at the back of the porous Ni sheet when the energy of incident ion beam was lower than 180 eV. When the energy of the incident ions increased, the positive ions dominated at the back of the porous Ni sheet. The production of negative hydrogen on Ni surface can't be explained by comparing the electron affinity of Ni and H. The charge transferring during the process of H atoms reflected from Ni surface was calculated by using constrained DFT (cDFT). The results show the production of negative hydrogen on Ni surface may well be due to heterogeneous electron density on the Ni surface. However, the influence of incident energy on the production of negative and positive hydrogen ions is unable to be explained by cDFT. The problem may be solved by using TDDFT which is able to capture the transfer of energy to electrons during the collision between atoms.

The nanosized Bi-doped SnO2/reduced graphene oxide 3D hybrids have been synthesized via one-step hydrothermal method. The structures, morphologies, photocatalytic activities of the as-prepared samples were discussed, respectively. The formation mechanism of the as-prepared hybrids was also proposed. Experimental results indicated that the usage amount of Bi2Sn2O7 obviously affected the photocatalytic performance of the as-prepared products. When it was 450 mg, the as-prepared sample possessed the band gap energy of 1.9 eV and the photocatalytic efficiency of 90% in 210 min for degradation of rhodamine B solution. In addition, triethylene tetramine and the as-prepared carbon hydrogel could act as reductant to synergistically reduce Bi2Sn2O7 into Bi-doped SnO2 particles during the formation of the hybrids.

The Xiarihamu mafic-ultramafic intrusion is situated in the East Kunlun Orogenic Belt (E-KOB), northern Tibetan Plateau, China, with Ni-Co sulfide mineralization mainly in orthopyroxenite and olivine orthopyroxenite. Whole-rock and mineral compositions show cyclic variations in drill-hole intersections through the Xiarihamu mafic-ultramafic intrusion. Microbeam X-ray fluorescence (XRF) mapping shows reverse zoning (Cr-poor core, Cr-rich rim) and oscillatory zoning (Cr-poor core, Cr-rich mantle and Cr-poor rim) in orthopyroxene of olivine orthopyroxenite and orthopyroxenite. Zoned orthopyroxenes are euhedral or subhedral, and there are relatively sharp interfaces between zones with distinct Cr contents. Crystal-size distribution (CSD) curves of orthopyroxenes in olivine orthopyroxenite show concave-upward curvature at size larger than 3.0 mm, and larger orthopyroxenes commonly display zoning, implying a secondary recrystallization and grain growth of larger orthopyroxenes. Quantitative analyses show that Cr and enstatite contents of cores are relatively lower, but incompatible element (e.g., Ti, Zr, Ga and Sr) contents of cores are higher than rims in reverse zoned orthopyroxenes, and chemical profiles of unzoned orthopyroxenes resemble those of rims (but different from those of cores) in reverse zoned orthopyroxenes. Chemical profiles of orthopyroxenes indicate that Cr zoning is not due to the change in Cr partitioning behavior between orthopyroxene and silicate melt, which shows significant temperature and redox dependence. Textural feature and crystal-size distribution of orthopyroxenes suggest the formation of Cr-rich zones attests to the multi-stage growth in the process of magma replenishment, rather than a reactive liquid flow model or in-situ trapped liquid overgrowth. Orthopyroxene zoning, together with compositional variation and intrusive relationship between olivine orthopyroxenite and orthopyroxenite imply that the Xiarihamu mafic-ultramafic intrusion was formed by multiple magma replenishments with magma varying roughly from a more evolved to a more primitive composition.

Inhalational anesthesia with sevoflurane for endotracheal intubation without muscle relaxant is now used widely for pediatric patients. This study assessed the efficacy and safety of induction with high concentration sevoflurane and of nasotracheal intubation without muscle relaxant in infants with increased or decreased pulmonary blood flow (PBF) and undergoing surgery for congenital heart diseases.Fifty-five infants aged 2 - 12 months, weighing 4.7 - 10.0 kg, and scheduled for congenital cardiac surgery were enrolled. Subjects were divided into those with increased (IPBF group, n = 29) and decreased (DPBF group, n = 26) pulmonary blood flow. All infants received inhalational induction with 8% sevoflurane in 100.0% oxygen at a gas flow rate of 6 L/min. Nasotracheal intubation was performed 4 minutes after induction. Sevoflurane vaporization was decreased to 4.0% for placement of a peripheral intravenous line and invasive hemodynamic monitors. Five minutes later, sedatives and muscle relaxant were administered and the vaporizer was adjusted to 2% for maintenance of anesthesia. Bispectral index (BIS) scores, circulatory parameters, satisfactory and successful intubation ratios, adverse reactions, and complications of intubation were recorded.Times to loss of lash and pain reflexes were longer for the DPBF group (P0.01). Satisfactory intubation ratios were 93.1% and 61.5% for the IPBF and DPBF groups, respectively (P = 0.008). Successful intubation ratios were 96.6% and 76.9% for the IPBF and DPBF groups, respectively (P = 0.044). Following sevoflurane inhalation, blood pressures decreased significantly in the IPBF group but remained stable in the DPBF group. BIS scores declined to similar stable values, and a "nadir BIS" was recorded for both groups. No obvious adverse reactions or complications of intubation were noted perioperatively.Induction with high concentration sevoflurane, although faster for infants with IPBF, is safe for infants with IPBF or DPBF. However, nasotracheal intubation without muscle relaxant after induction with high concentration sevoflurane is less successful and less satisfactory for infants with DPBF and should be used with caution in this patient group.

To evaluate the clinical result of the frontalis muscle fascial flap passing through the pulley of orbital septum for correction of severe blepharoptosis.57 eyes in 52 cases with congenital severe blepharoptosis were treated in recent two years. After the frontalis muscle fascial flap was prepared beneath the orbicularis oculi muscle, the pulley was created by two parallel horizontal incision on the orbital septum at the upper orbital rim and 1 cm under the upper rim. The frontalis muscle fascial flap was then pulled down behind the pulley and out to be attached to the upper margin of tarsal plate.The following-up period was 3-6 months. Satisfactory cosmetic result was achieved in 52 eyes. Three eyes had ptosis relapse and 2 eyes had unnatural contour of the palpebral margin which required another corrective operation. No other complication was observed.The pulley created by the orbital septum makes the traction lines of the frontalis muscle fascial flap in a similar direction as the natural movement of levator muscle. So both the postoperative static and dynamic appearance of the upper lid is more natural. The technique is very practicable in correction of blepharoptosis.

To study the feasibility of the modified osteotomy of transcranial orbitotomy in the treatment of intraorbital tumor.We treated 8 patients with intraorbital tumor during six years. By the bicoronary incision, all cases underwent double bone flap osteotomy on the frontal bone: the superior orbital rim bone flap and roof flap instead of single fronto-orbital bone flap in the conventional transcranial orbitotomy. After removal of bone flaps, intracranial and intraorbital operation was performed. Then, two bone flaps were reduced respectively and fixated with titanic micro-plates and nails. At last, the scalp flap was sutured.The operative field was very well exposed. It was found that the retrobulbar tumor was located at the superolateral, median and superonasal area respectively, which was coincided with the preoperative CT and MRI. The tumor included adenocarcinoma of the lacrimal gland, neurinoma, meningioma, and cavernous hemangioma. Four patients had blood transfusion during the operation. No other postoperative complications happened except 3 cases of diplopia and one case of blindness. After 3 to 6 months follow up, diplopia of the 3 cases gradually disappeared. Of the 8 cases, 6 reached the same visual acuity as the preoperative state. One decreased visual acuity and one lost light perception. There was well-balanced fronto-orbital appearance and eyeball position compared with the healthy side in all cases.This surgical method for the treatment of intraorbital tumor is safe with well-exposed operative field. It has advantages not only in simpleness and less trauma, but also in keeping orbital roof and anterior fossa intact and decreasing complications.

We report the rare occurrence of herpes zoster reactivation after facial trauma. Herpes zoster appeared in painful groups of distended vesicles containing clear fluid on an erythematous base within the secondary division of the trigeminal nerve. The patient was treated with acyclovir (intravenous, 250 mg, every 8 hours) combined with topical steroids and anti-neuropathic pain medication. The zoster-associated neuralgia subsided gradually 1.5 months after diagnosis. We illustrate this unique case to highlight the fact that reactivation of the varicella zoster virus from childhood chicken pox can reappear at a traumatic site in late adulthood.