Absorption characteristics,model,and molecular mechanism of hydrogen sulfide in morpholine acetate aqueous solution

The solubility of H_(2)S was measured in solutions of N-butyl-N-methylmorpholine acetate([Bmmorp][Ac])containing 20%-40%(mass)water at experimental temperatures ranged from 298.15 to 328.15 K and pressures up to 320 k Pa.The total solubility of H_(2)S increased with higher temperatures,lower pressures,and reduced water content.The reaction equilibrium thermodynamic model was used to correlate the solubility data.The results indicate that the chemical reaction equilibrium constant decrease with increasing water content and temperature,whereas Henry constant increase with increasing water content and temperature.Compared with other ionic liquids,H_(2)S exhibits a higher physical absorption enthalpy and a lower chemical absorption enthalpy in[Bmmorp][Ac]aqueous solution.This suggests that[Bmmorp][Ac]has a strong physical affinity for H_(2)S and low energy requirement for desorption.Quantum chemical methods were used to investigate the molecular mechanism of H_(2)S absorption in ionic liquids.The interaction energy analysis revealed that the binding of H_(2)S with the ionic liquid in a1:2 ratio is more stable.Detailed analyses by the methods of the interaction region indicator and the atoms in molecules were conducted to the interactions between H_(2)S and the ionic liquid.

Surface-engineering of layered LiNi_(0.815)Co_(0.15)Al_(0.035)O_2 cathode material for high-energy and stable Li-ion batteries

Surface engineering is an effective strategy to restrain the generation of rocksalt NiO phase on surface of layered LiNi_(0.815)Co_(0.15)Al_(0.035)O_2(NCA) primary nanoparticles, a representative Ni-rich layered oxides cathode materials. Herein, we demonstrate the kilogram-scale synthesis of few-layer reduced graphene oxide(rGO) conformably coated NCA primary nanoparticles cathode materials by a mechanical wet ball-milling strategy. The lightening rGO coating layer effectively avoids the direct contact of electrolyte and NCA with rapid electrons transfer. As a result, the as-obtained NCA@rGO hybrids with only 1.0 wt% rGO content can deliver a high specific capacity(196 mAh g^(-1) at 0.2 C) and fast charge/discharge capability(127 mAh g^(-1) at 5 C), which is much higher than the corresponding NCA nanoparticles(95 mAh g^(-1) at 5 C). Even after100 cycles at 1 C, 91.7% of initial reversible capacity is still maintained. Furthermore, a prismatic pouch cell(240 mAh) is also successfully assembled with the commercial graphite anode.

杜诗“青春作伴好还乡”之“青春”另解

杜诗“白日放歌须纵酒,青春作伴好还乡”之“青春”,一般解作“大好春光”,盖因“杜甫作此诗时,正值春天。春和景明,伴人归乡,颇不寂寞”。不过,考杜甫《拨闷》、李白《哭宣城善酿纪叟》《襄阳歌》、韩愈《感春四首》、杜牧《清明》诸诗,“春”均可代“酒”。若将“青春”释为“青绿美酒”,全句不仅语意贯通,且属对巧妙,整首诗亦顿开生面。

Visual Relationship Detection with Contextual Information

Understanding an image goes beyond recognizing and locating the objects in it,the relationships between objects also very important in image understanding.Most previous methods have focused on recognizing local predictions of the relationships.But real-world image relationships often determined by the surrounding objects and other contextual information.In this work,we employ this insight to propose a novel framework to deal with the problem of visual relationship detection.The core of the framework is a relationship inference network,which is a recurrent structure designed for combining the global contextual information of the object to infer the relationship of the image.Experimental results on Stanford VRD and Visual Genome demonstrate that the proposed method achieves a good performance both in efficiency and accuracy.Finally,we demonstrate the value of visual relationship on two computer vision tasks:image retrieval and scene graph generation.

Stacked Attention Networks for Referring Expressions Comprehension

Referring expressions comprehension is the task of locating the image region described by a natural language expression,which refer to the properties of the region or the relationships with other regions.Most previous work handles this problem by selecting the most relevant regions from a set of candidate regions,when there are many candidate regions in the set these methods are inefficient.Inspired by recent success of image captioning by using deep learning methods,in this paper we proposed a framework to understand the referring expressions by multiple steps of reasoning.We present a model for referring expressions comprehension by selecting the most relevant region directly from the image.The core of our model is a recurrent attention network which can be seen as an extension of Memory Network.The proposed model capable of improving the results by multiple computational hops.We evaluate the proposed model on two referring expression datasets:Visual Genome and Flickr30k Entities.The experimental results demonstrate that the proposed model outperform previous state-of-the-art methods both in accuracy and efficiency.We also conduct an ablation experiment to show that the performance of the model is not getting better with the increase of the attention layers.

An Attention-Based Recognizer for Scene Text

Scene text recognition(STR)is the task of recognizing character sequences in natural scenes.Although STR method has been greatly developed,the existing methods still can't recognize any shape of text,such as very rich curve text or rotating text in daily life,irregular scene text has complex layout in two-dimensional space,which is used to recognize scene text in the past Recently,some recognizers correct irregular text to regular text image with approximate 1D layout,or convert 2D image feature mapping to one-dimensional feature sequence.Although these methods have achieved good performance,their robustness and accuracy are limited due to the loss of spatial information in the process of two-dimensional to one-dimensional transformation.In this paper,we proposes a framework to directly convert the irregular text of two-dimensional layout into character sequence by using the relationship attention module to capture the correlation of feature mapping Through a large number of experiments on multiple common benchmarks,our method can effectively identify regular and irregular scene text,and is superior to the previous methods in accuracy.

Effects of in-situ TiB_(2)particles on machinability and surface integrity in milling of TiB_(2)/2024 and TiB_(2)/7075 Al composites

In-situ ceramics particle reinforced aluminum matrix composites are favored in the aerospace industry due to excellent properties.However,the hard ceramic particles as the reinforcement phase bring challenges to machining.To study the effect of in-situ TiB_(2)particles on machinability and surface integrity of TiB_(2)/2024 composite and TiB_(2)/7075 composite,milling experiments were performed,and compared with conventional 2024 and 7075 aluminum alloys.In-situ TiB_(2)particles clustered at the grain boundaries and dispersed inside the matrix alloy grains hinder the dislocation movement of the matrix alloy.Therefore,the milling force and temperature of the composites are higher than those of the aluminum alloys due to the increase of the strength and the decrease of the plasticity.In the milling of composites,abrasive wear is the main wear form of carbide tools,due to the scratching of hard nano-TiB_(2)particles.The composites containing in-situ TiB_(2)particles have machining defects such as smearing,micro-scratches,micro-pits and tail on the machined surface.However,in-situ TiB_(2)particles impede the plastic deformation of the composites,which greatly reduces cutting edge marks on the machined surface.Therefore,under the same milling parameters,the surface roughness of TiB_(2)/2024 composite and TiB_(2)/7075 composite is much less than that of2024 and 7075 aluminum alloy respectively.Under the milling conditions of this experiment,the machined subsurface has no metamorphic layer,and the microhardness of the machined surface is almost the same as that of the material.Besides,compared with 2024 and 7075 aluminum alloy,machined surfaces of TiB_(2)/2024 composite and TiB_(2)/7075 composite both show tensile residual stress or low magnitude of compressive residual stress.

Interactions between cadmium and multiple precipitates in an Al-Li-Cu alloy:Improving aging kinetics and precipitation hardening

This work demonstrates significant improvements in both the aging kinetics and precipitation hardening of an Al-Li-Cu alloy with the minor addition of Cd(0.06 at.%).The precipitation hardening effect of T1 precipitates in casting Al-Li-Cu alloys has long been ignored since it is difficult to achieve a high number density of fine precipitates without a large number of dislocations.A detailed transmission electron microscopy investigation shows that the Cd addition has changed the distribution of T1 precipitates from the conventional uneven distribution near dislocations or grain boundaries to a more homogeneous manner.Most of the Cd-rich nanoparticles were observed at the broad face and/or terminal of the T1 platelets.It is highly likely that these nanoparticles act as heterogeneous nucleation sites,which consequently leads to a higher number density of T1 precipitates.Moreover,Cd atoms were preferentially segregated withinδprecipitates,which can be attributed to the strong bonding between Li and Cd.The interactions between Cd and the T1(Al2CuLi)andδ′(Al3Li)precipitates in Al-Li-Cu alloy are first reported.The present study may propose a new mechanism to effectively improve precipitation kinetics and therefore the age-hardening effect of Al-Li-Cu alloys.

MpbR,an essential transcriptional factor for Mycobacterium tuberculosis survival in the host,modulates PIM biosynthesis and reduces innate immune responses

Mycobacterium tuberculosis possesses unique cellular envelope components that contribute to bacterial escape from host immune surveillance.Phosphatidylinositol mannosides(PIMs)and their higher derivatives are important molecules implicated in host-pathogen interactions in the course of tuberculosis.However,the biosynthetic regulation of these specific lipids and its effect on the bacterial fate in the infected host remain unclear.Here,we show that a hypothetical M.tuberculosis transcriptional factor designated as MpbR negatively regulates two transporter genes and affects mycobacterial PIM biosynthesis and biofilm formation.MpbR inhibits the accumulation of acylated PIM lipids and triggers the mycobacterium to reduce the production of reactive oxygen species and NO during infection,which enhances the survival of M.tuberculosis in macrophages.MpbR deletion reduces M.tuberculosis lung burdens and inflammation of infected mice.These findings provide new insights into the regulation of mycobacterial lipid metabolism and its correlation with pathogenesis of M.tuberculosis.