In the context of climate change, problem water scarcity is becoming increasingly serious, and improving efficiency resources use an important measure to alleviate this problem. The evaluation utilization has become basis resource management. Data envelopment analysis (DEA) analytic hierarchy process (AHP) are widely used in efficiency. However, one these methods mostly for evaluation, which cannot reflect influence both objective subjective factors. Therefore, study, we propose a index...

Abstract An efficient procedure for the asymmetric allylic amination of Morita–Baylis–Hillman carbonates with cyclic imides catalysed by commercially available cinchona alkaloids is reported. It proves to be a facile protocol that affords α‐methylene β‐amino esters good‐to‐excellent enantioselectivities (up 94 % ee ) and in high yields 97 %). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Streamflow modelling is one of the most important elements for management water resources and flood control in context future climate change. With advancement numerical weather prediction modern detection technologies, more high-resolution hydro-meteorological data can be obtained, while traditional physical hydrological models cannot make full use them. In this study, a hybrid deep learning approach proposed simulation daily streamflow two mountainous catchments Daqing River Basin, northern...

An asymmetric exo-Diels-Alder reaction of α-methylene carbonyl compounds, generated in situ from stable methiodide salts Mannich bases, with 2,4-dienals, has been developed through trienamine activation a chiral secondary amine. A spectrum spirocyclanes high molecular complexity was efficiently constructed moderate to excellent diastereo- and enantioselectivity.

Crop resilience refers to the adaptive ability of crops resist drought at a certain level. When degree stress did not exceed range crop, crop could recover even normal growth after rehydration. However, assessment lacks considerations on mechanisms. Focusing suitable maize planting areas in China, this study took relative soil humidity (RSH) as index screen and rehydration events, identified mechanism under conditions, determined correlation between RSH. The results shown that strongest were...

Crop resilience refers to the adaptive ability of crops resist drought at a certain level. Currently, most research focuses on changes in root or photosynthesis traits after and rehydration. Still, persistence effect (drought period (T2) - rehydration (T3) harvest (T4)) stress quantitative estimation is still unclear. Field experiments were conducted this study determine effects above-ground below-ground growth indicators summer maize different levels durations drought. Next, an evaluation...

This work introduces an innovative seismic isolation system named the convex friction (CFS). newly introduced has a sliding concavity with circular cone-type surface, and exhibits some distinct features compared to conventional techniques, such as increased uplift stability, improved self-centring capacity, resonance dodge when subjected near-fault earthquakes. A series of comprehensive analytical numerical investigations are performed verify these CFS. First, force–displacement relation CFS...

Climate change and human activities are two important factors affecting surface runoff. In water resource management planning, it is generally to separate the contribution of these when assessing runoff changes. The Changbai Mountain area rich in resources an hydropower energy base for Northeast China. This study used Sen’s slope estimator explore trends precipitation evapotranspiration from 1960 2016, results showed a downward trend upward evaporation most areas. mutation point annual time...

SLAM (Simultaneous Localization and Mapping) is mainly composed of five parts: sensor data reading, front-end visual odometry, back-end optimization, loopback detection, map building. And when estimated by odometry only, cumulative drift will inevitably occur. Loopback detection used in classical SLAM, if not detected during operation, it possible to correct the positional trajectory using loopback. Therefore, address problem this paper adds Indoor Positioning System (IPS) optimization uses...

Microstructure evolution of P92 heat-resistant steel during long-term service has high influence on the creep property. In this paper, samples were aged at 898 K for 10,000 h, 15,000 h and 25,000 h. The effect thermal ageing microstructure was analysed through optical microscopy scanning electron microscopy. behaviour specific shear stresses (14.7 MPa, 20 25.6 41 MPa) investigated helicoid-spring testing. relationship between properties discussed. results demonstrated that basic morphology...

Abstract In order to analyze the effect of thermal ageing on creep rupture mechanism and establish a method for predicting life P92 heat-resistant steel under ageing, tests were performed specimens, aged at 650 °C different times applied stresses. Optical microscopy scanning electron utilized observe microstructure after rupture. Voids cracks distributed in grains before whereas voids clearly around M 23 C 6 precipitates Laves phase along sub-grain boundaries ageing. The damage tolerance...

Water is crucial for high transformation efficiency in the title reaction catalyzed by α,α-diphenylprolinol derivative 1. Excellent stereoselectivities were observed a broad spectrum of substrates (see scheme; TMS=trimethylsilyl, Tos=p-toluenesulfonyl). A diverse range chiral piperidine derivatives and other valuable compounds can be prepared from hemiaminal products. Detailed facts importance to specialist readers are published as "Supporting Information". Such documents peer-reviewed, but...

Abstract In this work, the effects of C, N, and Al on microstructures creep properties Fe–Cr–Al–Nb–W ferritic alloys were investigated through scanning electron microscopy, x-ray diffractometry, as well uniaxial testing hardness testing. The results demonstrated that matrix heat-resistant steel was ferrite, while precipitation phases Laves phases, M 23 C 6 carbides MX nitride phases. precipitated at grain interior, boundary around N affected microstructure steel. As content increased or...

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at glance that was extracted from about 100 leading journals. To access of an article which published elsewhere, please select “Full Text” option. The original trackable via the “References”

Abstract Labile α‐methylene carbonyl compounds are generated in situ from bench‐stable methiodide Mannich salts.

A hybrid approach is presented in this paper to segmenting the brain matter, as assessed by magnetic resonance (MR) imaging, into three major tissue classes of gray matter (GM), white (WM), and cerebrospinal fluid (CSF). First, a fuzzy clustering algorithm used divide original T1 T2 weighted MR images groups with similar intensity distributions. Then multiple level reasoning method adopted label pixels cerebral image one classes. Finally, symmetric index calculated for these show possible...

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at glance that was extracted from about 200 leading journals. To access of an article which published elsewhere, please select “Full Text” option. The original trackable via the “References”

Bio-surfactant rhamnolipid produced by Pseudomonas aeruginosa was investigated in the process of biodegradation n-hexadecane. The result showed that solubility n-hexadecane have a linear relationship with when below or above critical micelle concentration (CMC). stronger CMC than CMC. Then, strains treated were applied degradation. results growth bacterium inhibited 75 mM (1 CMC) rhamnolipid. However, bacterial 750 (10 accelerated There no degradation phenomenon occurred without being This...