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•Standard molar volumes of teotropine (tetramethylenediethylenetetramine – TMDETA) in water were determined densimetrically.•Density measurements were performed at temperatures from ...278.15 K to 318.15 K (with a step of 10 K) at ambient pressure.•Like the related aminal solute urotropine (hexamethylenetetramine – HMTA), TMDETA has a structure-making effect in water.•Structure packing of the hydration complex formed becomes denser and thermally more stable when going from HMTA to TMDETA.•Structure-forming effect (due to hydrophobic effects and H-bonding) is greater in aqueous TMDETA as a bulkier aminal solute.
The densities of aqueous solutions of tetramethylenediethylenetetramine (the teotropine pharmaceutical) with the solute molality from (0.01 to 0.12) mol·(kg water)−1 were measured at T = (278.15, 288.15, 298.15, 308.15, and 318.15) K and p = 0.1 MPa. The uncertainty in density measured using the Anton Paar DMA 5000 M densimeter (equipped with an oscillating U-tube) was estimated to be 0.03 kg m−3 or lower. The standard (apparent at infinite dilution) molar volumes and expansibilities of teotropine were computed. Based on the analysis of contributions to the standard molar volume in terms of the Scaled Particle Theory was confirmed that a bulkier molecule of teotropine interacts with water stronger than it does a molecule of urotropine or hexamethylenetetramine – the related aminal (cage-like) compound.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The expansibility and mechanical properties of shale are significantly influenced by water-based muds (WBMs); thus, it is necessary to mitigate this effect to avoid borehole instabilities in drilling ...operation. Potassium chloride (KCl) is usually used as inhibitor to reduce hydration of shales. In this study, we investigated the inhibitory efficiency of KCl on shale through a series of experiments, including dynamic linear swelling (DLS) tests and uniaxial compressive strength (UCS) tests, to provide reference for the design of WBMs. These tests were conducted on shale samples soaked in KCl solution for 24, 48, 72, and 96 h with saline concentrations of 0%, 2%, 4%, 6%, and 8%. Experimental results show that samples with microcracks and bedding fissures have the highest swelling increase and the largest strength reduction after immersion in solution. The swelling potential decreased with increasing KCl concentration. In addition, KCl exhibited a certain inhibitory effect on the weakening of the mechanical properties of samples. An increase in the KCl concentration increases the compressive strength and elastic modulus, and decreases the Poisson's ratio. However, in terms of homogeneous samples, the UCS test results show that exposure to water is weakly related to weakening of the mechanical properties of shale samples. We found that immersing the shale in KCl solution for a longer time decreases the compressive strength, increases the Poisson's ratio, and decreases the elastic modulus.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The hygroscopicity of expanded vermiculite is one of major influence factors for thermal insulating performance. To explore the water absorption properties of expanded vermiculite prepared via ...electrical heating method, heating temperature effect on the hygroscopicity of expanded vermiculite was investigated under various humidity circumstances. The influencing mechanisms were analyzed by means of Thermogravimetric Analysis-Differential Scanning Calorimeter technique (TG-DSC), Fourier-Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), and the Brunauer–Emmett–Teller technique (BET) for the measurement of the specific surface area. The results of water absorption experiments indicated that the hygroscopicity of vermiculite showed an inversely proportional relationship to heating temperature and the water absorption content of EV-900 was only 6.206 mg/g with a dramatic decline of 91.5% in comparison with that of RV. This decline of water absorption capacity was mainly attributed to the decrease of interlamellar spacing and specific surface area. In addition, environment humidity had a significant effect on water absorption capacity and velocity. The water absorption content of EV-400 sample increased dramatically from 48.414 mg/g at the humidity of 55%–72.929 mg/g at the humidity of 95%, and the equilibrium time reduced from 3 h to 0.5 h. This study will provide a new perspective and theoretical guidance for the development of vermiculite based thermal insulating materials.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Information technology diffusion (ITD) is essential for promoting the sustainable development of technologies and helping technology owners gain a competitive advantage. The web-based development of ...technology and the digital transformation needs of multidisciplinary markets simultaneously drive the increasing convergence and expansibility of information technology (IT). However, whether these two technological characteristics can contribute to the diffusion of early-stage IT and how they influence the further diffusion of IT that has already diffused on a large scale are yet to be thoroughly investigated. We argue that the impact of technology convergence on ITD is heterogeneous when distinguishing between low- and high-ITD scenarios, as is technology expansibility. Our quantile regression estimates use a dataset about Internet of Things (IoT) patents authorized by the Chinese Patent Office from 2009 to 2019. The results show that increased technology convergence benefits ITD in high-ITD scenarios but does not affect ITD in low-ITD scenarios. Technology expansibility negatively impacts ITD in high-ITD scenarios and positively impacts ITD in low-ITD scenarios. This study broadens the theoretical paradigm of “technological characteristics and ITD” from the domain perspective. It inspires information technology owners to formulate sustainable strategies related to ITD according to technology convergence and expansibility.
•Enriching the study of IT management and technology diffusion through the dual lens of convergence and application domain.•Increased technology convergence is beneficial for IT diffusion in high-diffusion scenarios, but has no effect in low-diffusion scenarios.•Increased technology expansibility promotes IT diffusion in low-diffusion scenarios while acting conversely in high-diffusion scenarios.•A quantile regression model is built and tested by data from the citation network of IoT patents, relevant patents' and companies' information.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The present work reports a novel hybrid modular floating structure (HMFS) system consisting of a certain number of outermost box-type modules and inner semi-sub modules. Semi-sub modules are ...connected with ball joints in both longitudinal and transverse directions. Box-type modules are connected with adjacent semi-sub modules with pitch hinges. Outermost box-type modules mainly function as wave energy converters (WECs) and breakwaters. Based on the rigid module and flexible connector (RMFC) method, the effects of different wave directions, longitudinal expansion, positions of modules and connectors on hydrodynamic responses of the HMFS system are emphatically investigated under typical sea conditions. The results indicate that for the layout of the HMFS system, the transverse direction is recommended to be consistent with wave direction with the highest occurrence probability in terms of comprehensive consideration of module motions, connector loads, mooring forces as well as wave energy power. The HMFS system shows good longitudinal expansibility for mild marine environments. The positions of modules and connectors have significant effects on their hydrodynamic responses, and the corresponding mechanism has been preliminary clarified. In addition, the statistic information of extreme hydrodynamic responses under representative wave directions has been comparatively analyzed for the ultimate limit state design of the HMFS system.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In the above paper, I have debated the reliability of the existing literature data on the standard (partial at infinite dilution) molar volumes and expansibilities of hexamethylenetetramine (HMT) in ...heavy water (D2O) and the corresponding D2O–H2O solvent isotope effects. Based mainly on the results of two works under comparison C.M. Romero and H.J. Mesa, J. Mol. Liq. 242 (2017) 244–248; Yu.P. Pankratov and V.K. Abrosimov, Russ. J. Phys. Chem. 71 (1997) 1263–1266, a general conclusion about the pronounced inconsistencies in the discussed quantities for the solute in both in (H2O + HMT) and (D2O + HMT) has been made. This fact initiated a necessity carrying out the additional high-precision densimetric study of these binary liquid systems, followed by estimating the volume-isotope characteristics of interest. Such a study has been done and its results are reported in the present work. Primarily, it is confirmed here the conclusion on the doubtfulness of results derived by both authors' groups being analyzed in comparison.
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•Densities of hexamethylenetetramine (HMT) solutions in H2O and D2O were measured.•Standard molar volumes and expansibilities for HMT were computed at 278–318 K.•Volume-isotopic effect undergoes a negative-to-positive sign inversion at ~ 290 K.•HMT hydration interpret as competition between structure-making/−breaking effects.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Deep learning-based no-reference image quality assessment (NRIQA) methods have demonstrated advanced performance. In this paper, a deep learning-based NRIQA method with strong error-aware and ...content-aware capabilities is proposed, which consists of Error-Aware Reconstruction Network (EARNet) module, Content Feature Extraction Network (CFENet) module, and Subjective Quality Regression Network (SQRNet) module. We first build a database to pre-train EARNet to obtain the ability to extract error features. For content features, CFENet pre-trained on large-scale image classification tasks is adopted to extract. The pre-trained EARNet and CFENet are serially connected with SQRNet so that the features received by SQRNet are both error-aware and content-aware. Extensive experimental results show that the proposed method achieves state-of-the-art performance on many well-known IQA databases. The robustness of the proposed method is verified on the large-scale Waterloo Exploration Database (WED), and its superiority is demonstrated by the group maximum differentiated (gMAD) competition game. Furthermore, we also verify that the proposed EARNet is highly extensible, which can further improve the performance of the existing deep learning-based NRIQA method.
•A blind image quality assessment method based on deep learning is proposed.•The proposed model has both error and content awareness.•The proposed method has advanced performance and high scalability.•Creatively designed a joint loss to guide the model in generating error maps.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Volumetric and acoustic studiesofCaptoprilin aqueous acetaminophen system.•The negative values of partial transfer volume, ΔtVΦo confirmed the strong interactions between captopril and ...acetaminophen.•Hydration number decline with temperature which is due to lose of electrostriction.•Results are discussed in terms ofmolecular interactionsbetween components.•The positive values of partial molar expansibility predict increasing electrostriction.
Captopril is an antihypertensive drug used to lower the blood pressure in living organisms. In order to arbitrate and understand the synergy between antihypertensive drug viz., captopril and antipyretic drug acetaminophen in aqueous system, the density and sound velocity at different temperatures (293.15 to 318.15) K with temperature interval of 5 K were measured using Anton Paar density sound velocity meter (DSA5000M). The experimental measured data were further used to calculate volumetric and acoustic parameters such as apparent and partial molar volume, apparent and partial molar isentropic compressibility, partial molar expansibility, Hepler’s constant, compressibility hydration number, and intermolecular free length. Positive values of apparent molar volume (ϕv) and negative values of apparent and partial molar compressibility (ϕk and ϕko) of captopril in water and aqueous acetaminophen solution has been shown strong intermolecular interactions in solutions. Negative values of Hepler's constant indicate the structure breaking behavior of drug in water.
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•Stronger ion-hydrophilic and hydrophilic-hydrophilic interactions exist in the solutions.•Aspartic acid acts as structure builder in presence of PS and SB.•Stronger ion-ion and ...ion-hydrophilic interactions occur in aq. SB than in aq. PS.•Formation of transition state for viscous flow is thermodynamically not favoured.
Aspartic acid (Asp), a nonessential amino acid has been taken for the present study. Solutions of different concentrations of aspartic acid were prepared by dissolving it in water and {water + (1.5, 2.0 and 2.5 m) Potassium sorbate (PS)/sodium benzoate (SB)}. Density and viscosity of the solutions were experimentally determined at T = (293.15, 298.15, 303.15, 308.15 and 313.15) K. Volumetric parameters like apparent molar volume (V∅), partial apparent molar volume (V∅0), partial apparent molar expansibility (E∅0) were computed by using standard formulations. Stronger ion-ion, ion-hydrophilic and hydrophilic-hydrophilic interactions between zwitterionic centers (COO- and NH3+) and polar groups of aspartic acid (COOH and NH2) and ions present in aqueous PS/SB are found to dominate the hydrophobic interactions between the nonpolar organic segments of amino acid and PS/SB. Structure building character of aspartic acid in presence of PS/SB are established by the positive values of Hepler’s constant (∂2V∅0/∂T2)P for all compositions of solutions. Positive viscosity B-coefficient (BJ) and negative (∂BJ/∂T)values further establish the structure building character of aspartic acid. Thermodynamic parameters for viscous flow (Δμ20,#,ΔS0,#andΔH0,#) suggest that transition state for viscous flow is less stable than the ground state and formation of transitions state is not thermodynamically favoured. Shifting of IR absorption band for O-H stretching due to H-bonding at 3300–3340 cm-1 confirms changes in solvent structure due to ion-ion and ion–solvent interactions occurring in the investigated systems.
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