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The paper investigates the causes, magnitude and damage caused by the flood as a result of the breaching of the east marginal embankment of the Taunsa Barrage. The flood frequency in the district of Muzaffar Garh located in south Punjab, Pakistan had serious impacts on human lives and their properties. To pursue this study, we used primary data, collected through questionnaire, formal interviews, field observations and secondary data, obtained through government departments and online open source databases. Furthermore, Landsat ETM+ imageries were used as input in the supervised classification in order to investigate the pre and post flooding land cover and land use. Hydrograph was used to analyze the flood limits and spatiotemporal change in river discharge for barrages. The results show an abnormal rainfall occurring in the month of July in the upper Indus Basin, which resulted in a massive discharge in the central Indus Basin. As a consequence, it exceeded the flood limits at the Taunsa Barrage, which resulted in the breaching of east marginal embankment. The flood caused a high number of human casualties and a total economic loss of 14.23 million US$ including a 6.8 million US$ agricultural loss. The study thus, gives insight on how authorities can devise a flood management plan in such a way to reduce the future impacts of riverine flood disasters in Muzaffar garh. [ABSTRACT FROM AUTHOR]

Laser shock peening (LSP) is an effective approach to eliminate tensile residual stress, improve microhardness and refine coarse grain in the welding zone, which can significantly improve the mechanical properties of the welded joint. In the present work, microhardness curves and residual stress distributions of the gas tungsten arc welded (GTAW) 316L stainless steel tube before and after LSP were presented and compared. Furthermore, typical microstructure morphologies in the near-surface layer of the welding zone, the heat affected zone (HAZ) and the base metal for both cases were characterized by optical microscope (OM) and transmission electron microscope (TEM) observations. Results indicated that microhardness and residual stress of the GTAW stainless steel tube were significantly improved by laser shock wave. In addition, the relationship between residual stress, microhardness and microstructure in the welding zone of the welded joint were presented. [ABSTRACT FROM AUTHOR]

Topography determines the nature of hydrodynamic processes and its changes potentially affect the water quantity and quality. This study assessed the spatiotemporal impacts of topography changes on hydrological and hydrodynamic characteristics of China's largest freshwater lake, Poyang Lake. Results from simulation of different channel erosion intensities indicated that topography changes induced hydrological and hydrodynamic variations with spatiotemporal heterogeneity. Water levels in the lake decreased and the effect was enhanced with stronger erosion intensities. The decrease in water level was significant during the dry period, but negligible during the wet period. Water levels decreased by an average of 0.90-1.1 m in the northern channel during the dry period, and 0.27 m and 0.20 m in the central and eastern lakes during the rising and recession periods. The changing water level further affected the distribution of water with the effect of gathering water to the channel from nearby areas. Moreover, channel erosion altered the lake-river interactions. During the dry period, outflow discharges increased as the channel conveyance capacity increased by 25-136%. In contrast, during the wet period, outflow discharges decreased as the inflow regulation volume increased by 3.8-8.2 x 108 m³. Particularly, backflow frequency and volume increased during the flooding period of the Yangtze River. In addition, the dry period in Poyang Lake was extended, and the frequency of low-water events increased significantly. This study demonstrated the spatiotemporal impacts of topographical changes on hydrodynamic processes in Poyang Lake, therefore providing a better understanding of variations in water regimes and lake-river interactions. [ABSTRACT FROM AUTHOR]

Abstract: Aims: This study aimed to strengthen the reducing equivalent generation in Klebsiella pneumoniae for improving 1,3‐propanediol (PDO) production. Methods and Results: Disruption of the arcA gene activated the transcription levels of the TCA cycle genes and thus increased the NADH/NAD+ ratio by 54·2%, leading to the improved PDO titre and yield per cell from 16·1 g l−1 and 4·0 g gDCW−1 to 18·8 g l−1 and 6·4 g gDCW−1 respectively. Further ldhA gene deletion eliminated lactate accumulation and promoted the PDO titre to 19·9 g l−1. Finally, the glucose effect was weakened by deleting the crr gene to enhance the co‐utilization of glucose and glycerol, resulting in the increased PDO production to 23·8 g l−1 with the glycerol conversion rate of 59·5%. The PDO titre in bioreactor was promoted from 61·2 to 78·1 g l−1. Conclusions: Deletions of the arcA and the crr genes showed positive effects on the TCA cycle activity and the co‐utilization of glucose and glycerol, leading to the strengthened reducing equivalent generation and the improved PDO titre by 47·8% in shaker. The PDO titre in the bioreactor was enhanced to 78·1 g l−1. Significance and Impact of the Study: This study provided novel information on generating reducing equivalent for the PDO biosynthesis by strengthening the TCA cycle and weakening the glucose effect in K. pneumoniae. [ABSTRACT FROM AUTHOR]

A laser direct metal deposition (DMD) repaired Fe-based alloy coating was treated by laser shock processing (LSP). The effects of LSP on microstructure, phases, surface micro-hardness, surface residual stress and wear-fracture performance of the laser DMD repaired coating were investigated. Results showed that no obvious microstructure and surface micro-hardness differences are detected after LSP; however, LSP increased martensite volume fraction, decreased surface tensile residual stress and improved the wear and fracture performance of the repaired coating. The mechanism of the effect of LSP on the wear performance of the repaired coating was also addressed. In addition, the influence of the reduced residual tensile stress on the creation of debris was explained by referring to a mathematical model on the creation and propagation of the debris. [ABSTRACT FROM AUTHOR]

To investigate the effects of overlapping rate on the residual stress relaxation following laser shock peening (LSP) of LY2 Al-alloy, a three-dimensional (3-D) finite element analysis (FEA) model using ABAQUS software is developed to simulate the residual stress relaxation under three kinds of applied cyclic loadings. Special attention is paid to the residual stress relaxation process of the LY2 Al-alloy sheet with different overlapping rates. Results show that residual stress relaxation is strongly dependent of overlapping rate of massive laser shock peening treatment, and the fluctuation rate decreases with increasing overlapping rate. For all overlapping rates, the most drastic relaxation exists at a depth of 0.40 mm away from the top surface. With the overlapping rate being greater than 50%, the surface residual stress exhibits a better uniformity, and a maximum of in-depth residual stress after relaxation remains unchanged for a given cyclic loading. In addition, the influence mechanism of overlapping rate on stress relaxation after the first cycle is revealed. [ABSTRACT FROM AUTHOR]

The aim of this paper was to investigate the relationship between ultrasonic signal and microstructural feature of typical defects in a 304 stainless steel powder fibre laser clad layer on 316L stainless steel. Three kinds of clad defects, including microcrack, blowhole, and shrinkage or loose structure, were found and analysed through microstructural observations and analyses. Special attention was paid to the typical echo characteristics of different clad defects. Furthermore, the relationship between three kinds of clad defects and the typical characteristics of ultrasonic echo was found, which may provide a novel approach for defect detection and quality evaluation in the laser clad layer. [ABSTRACT FROM AUTHOR]

The effects of warm laser peening at different treating temperatures on damping capacity of Ti-6Al-4V titanium alloy were investigated based on the experimental study, the mechanism of damping capacity improvement on Ti-6Al-4V alloy treated by warm laser peening was discussed; moreover, the compressive residual stress (CRS) and its relaxation under vibration condition were simulated by finite element method (FEM), the stability of residual stress in Ti-6Al-4V titanium alloy subjected to warm laser peening processing was revealed based on the creep theory. It is shown that high dislocation density obtained by warm laser peening under the temperature of dynamic strain aging (DSA) is a critical factor for damping capacity improvement. Owing to higher damping capacity introduced by warm laser peening, the vibration stress is reduced and thus causes a lower creep rate and a slower residual stress relaxation speed than laser peening at room temperature. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the friction and wear properties of ZL109 Al-Si alloy treated by laser peen texturing. Firstly, the texture patterns composed of microdimples with different surface area densities were produced by laser peen texturing. Then the friction and wear characteristics of the textured surfaces were detected by a pin-on-disk reciprocating tribometer at dry sliding condition, and the anti-wear mechanism of laser peen textured samples was discussed based on the observation of surface topographies as well. The results show that the depth of the microdimples was positively correlated with the laser energy. The friction coefficient and the wear volume of the textured surface were reduced. In addition, less abrasive particles, adhered materials, plastic flow and gluing were found in the surface topography after laser peen texturing. laser peen texturing process can improve the friction and wear performance of ZL109 Al-Si alloy at dry condition. [ABSTRACT FROM AUTHOR]

Superconducting Fault Current Limiter (SFCL) is an attractive appliance for modern electrical power system. A 10.5 kV/1.5 kA three-phase HTS fault current limiter was developed by IEE, CAS. This improved rectifier-type SFCL with HTS coil of 6.25 mH is going on a demonstrated long-term reliable operation in a real 10.5 kV substation located in Hunan, China. In a three-phase-to-ground short circuit test of grid, the prospective fault current of 3.5 kA was limited to 635 A at the pre-setup short-circuit point successfully. [ABSTRACT FROM AUTHOR]

We have previously demonstrated that syngeneic marrow mixed with H-2 haploidentical marrow transplantation could provide not only protection against graft-versus-host disease (GVHD) but also anti-leukemic (GVL) effects in mice. In the present studies, we report clinical observations using autologous marrow mixed with HLA-haploidentical allogeneic marrow transplantation for treatment of patients with malignant blood diseases. Sixteen cases, including 12 with acute leukemia and four with advanced malignant lymphoma, were treated by autologous marrow, which was purged in vitro by hyperthemia (42.5°C for 70 min) following incubation for 5 days with interleukin 2 (IL-2) in liquid culture and mixed with HLA haploidentical marrow cells from their sibling or parent. Acute GVHD was not observed in any patient after transplantation. Hematological rescue in the clinical setting was demonstrated in all cases but one who died early from hepatic veno-occlusive disease (VOD). Five cases who were transplanted at the time of CR2 or CR3 and in advanced phase of lymphoma, relapsed 4 to 7 months after transplantation. The relapse rate was 31.3%. None of eight patients who received allogeneic BMT within 2 h after ABMT relapsed wth median follow-up of 12 months and two of them died from procedure-related complications. Seven cases are still alive and disease-free with a median follow-up of 12 months. Mixed chimerism was found in 3/6 cases, who had different sex donors, by analysis of sex chromosomes. These results show that mixed transplantation is a safe, effective and new approach to treating patients with malignant tumors. In order to detect the effects of GVL, studies are now in progress in our clinic. [ABSTRACT FROM AUTHOR]

To investigate the clinicopathologic characteristics of primary liver cancer (PLC) in young adults, 77 patients aged 35 or younger were compared with 603 patients older than 35 years during the same period. In the young patients, PLC showed: (1) a low incidence detected at mass survey (young 15.6% vs older 28.7%, P < 0.05); (2) a low level of history of hepatitis (young 36.8% vs older 66.3%, P < 0.01); (3) a high incidence of positivity for hepatitis B surface antigen (HBsAg) (young 79.2% vs older 67.6%, P < 0.05); (4) a relatively low incidence of associated cirrhosis (young 64.9% vs older 90.7%, P < 0.01); (5) larger tumor size (PLC > 5 cm; young 87.0% vs older 73.0%, P < 0.01); and (6) a more advanced stage of the disease according to the TNM classification (stage III; young 29.9% vs older 18.2%, P < 0.05). It is suggested that hepatitis B virus (HBV) may play an important role in the development of PLC without associated liver cirrhosis in young patients. Close periodic surveillance of young adults who are positive for HBsAg is important to detect PLC at an early stage. [ABSTRACT FROM AUTHOR]

A method called masked laser ablation (MLA) was proposed to fabricate a micro-dimple array on a substrate surface with a pulsed Nd:YAG laser. Micro-dimple arrays were successfully fabricated on the surface of Ti6Al4V samples both in air and water. The aim of this paper was to investigate the influence of processing parameters on the morphology of micro-dimples, spatter deposition, micro-dimple depth and ablation rate. Contrast experiments were conducted to evaluate the effects of masks. Results showed that the shape of micro-dimples in air could be affected by the overlapping of spatter between the adjacent micro-dimples, while in water it is nearly copied from the mask. The bottom of the micro-dimple fabricated in water was coarse but the periphery was clean. The spatter deposition extremely depended on the laser intensity, pulse numbers and surroundings. Discussions about the existence of masks were carried on. [ABSTRACT FROM AUTHOR]

The friction coefficient and wear resistance of non-smooth surface with different conditions are studied in this work. First, the effects of groove spacing on the friction behavior and wear resistance of the non-smooth surface are investigated. Second, the effects of massive laser shock peening (LSP) impact on the dry sliding wear performance of the non-smooth surface manufactured by laser surface texture (LST) are evaluated. In addition, the worn surfaces and typical microstructure in the top surface layer of all samples were characterized by field emission scanning electron microscope (SEM) with an EDS elemental analysis and transmission electron microscopy (TEM). The influence process of groove spacing and LSP on the friction behavior and wear resistance of T9 tool steel are also analyzed and discussed. [ABSTRACT FROM AUTHOR]

Numerical simulation and experimental investigation of laser-MIG hybrid angle-welding low-carbon 1.5-mm-thin SPCC steel sheets are presented in this work. The transient simulation analysis provides an access to the thermal-fluid phenomena prediction by employing a hybrid three-dimensional heat source model. Special attention is paid to the melt dynamic behaviors within the triangular molten pool affected by the Marangoni convection. The simulation results show that the temperature and its gradient distribution are symmetrical with respect to the laser beam, which is validated well by the experimental study. The microstructure of the welded joints was analyzed by scanning electron microscopy and transmission electron microscopy. The results show that the cross-section microstructures of welded joint are mainly composed of the weld zone, narrow heat-affected zone, and substrate. The semielliptic-like molten pool shape is consistent with that of the simulated results. The finer microstructure in the weld bead results from the rapid cooling rate of laser welding confirmed by the FEM calculation. The columnar and equiaxed dendrites are formed in the peripheral and central region of the molten pool, which is beneficial for the improvement of the microhardness.

Aims: This study aimed to strengthen the reducing equivalent generation in Klebsiella pneumoniae for improving 1,3-propanediol (PDO) production., Methods and Results: Disruption of the arcA gene activated the transcription levels of the TCA cycle genes and thus increased the NADH/NAD + ratio by 54·2%, leading to the improved PDO titre and yield per cell from 16·1 g l -1 and 4·0 g gDCW -1 to 18·8 g l -1 and 6·4 g gDCW -1 respectively. Further ldhA gene deletion eliminated lactate accumulation and promoted the PDO titre to 19·9 g l -1 . Finally, the glucose effect was weakened by deleting the crr gene to enhance the co-utilization of glucose and glycerol, resulting in the increased PDO production to 23·8 g l -1 with the glycerol conversion rate of 59·5%. The PDO titre in bioreactor was promoted from 61·2 to 78·1 g l -1 ., Conclusions: Deletions of the arcA and the crr genes showed positive effects on the TCA cycle activity and the co-utilization of glucose and glycerol, leading to the strengthened reducing equivalent generation and the improved PDO titre by 47·8% in shaker. The PDO titre in the bioreactor was enhanced to 78·1 g l -1 ., Significance and Impact of the Study: This study provided novel information on generating reducing equivalent for the PDO biosynthesis by strengthening the TCA cycle and weakening the glucose effect in K. pneumoniae., (© 2018 The Society for Applied Microbiology.)