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Sodium oxalate (Na2C2O4) is an excellent phosphorus-free agent, but in sodium oxalate-containing detergents with sodium dodecylbenzene sulfonate (SDBS) and sodium carboxymethyl cellulose (CMC), significant ash deposition occurs on cotton fabrics. SDBS is the main anionic surfactant in modern detergents and cotton fiber is the most commonly used textile fiber. In this study, sodium lignosulfonate (LS) was investigated for its ability to prevent redeposition in SDBS-Na2C2O4-CMC-LS formulations. The effects of LS on ash content, whiteness, optimum washing temperature, calcium oxalate morphology, zeta potential and surface tension were carefully analyzed. The results showed that the addition of LS significantly improved the prevention of ash deposits on cotton fibers. The ash content was less than 0.46%and a small amount of particles were scattered on the cotton fibers. LS showed good dispersibility but had little effect on the washing power and zeta-potential. [ABSTRACT FROM AUTHOR]

Fischer-Tropsch syncrude prepared via the Fischer-Tropsch synthesis (FTS) using a Fe-based catalyst is featured by its high content of linear α-olefins (C5-C13). The utilization of C6-C8 α-olefins for the synthesis of alkyl benzene sulfonate surfactants was performed in the present work via dimerization, benzene alkylation, and sulfonation. The effects of the reaction conditions on benzene alkylation over a trimethyl amine hydrochloride-acidic anhydrous aluminum chloride ionic liquid catalyst (Et3NHCl-AlCl3) have been studied in detail using C6 α-olefin dimers as a model alkylation agent. Under the optimal reaction conditions (molar ratio of AlCl3 to Et3NHCl = 2, catalyst loading = 0.29 mol %, reaction temperature = 30 °C, and molar ratio of benzene to C6 α-olefin dimer = 10) the conversion of the C6 α-olefin dimer was 100% and the selectivity toward the mono alkylbenzene product was 91.0%. C6-C8 α-olefin dimer alkylbenzene sulfonates (C6-C8 DBS) were synthesized via sulfonation using chlorosulfonic acid and characterized using Fourier Transform Infrared (FT-IR) spectroscopy and Liquid Chromatography-Mass Spectrometry (LC-MS). The surfactant properties of the C6-C8 DBS, including their equilibrium and dynamic surface tension, foaming, wetting and emulsifying capabilities, were closely explored and compared with a commercial linear alkylbenzene sulfonate (LAS). The limiting surface tension (γCMC = 34.62 mN m-1) and critical micelle concentration (CMC = 2.15 mmol L-1) of C6 α-olefin dimer alkylbenzene sulfonate (C6-DBS) were similar to those of LAS. Upon increasing the hydrocarbon chain length, the γCMC of C6-DBS, C7-DBS, and C8-DBS remained unchanged, while the CMC decreased. C6-C8-DBS exhibited foaming, emulsifying, and wetting properties comparable to LAS. [ABSTRACT FROM AUTHOR]

In this work, we have investigated the washing performance of sodium oxalate-based detergents containing different enzymes (protease, lipase and cellulase). The results show that sodium oxalate-based detergents with enzymes have a better washing performance than formulations containing the conventional builder STPP and zeolite 4A. For sodium oxalate-based with protease, the amount of sodium oxalate and protease have a significant effect on the detergency. Lipase can improve detergency of sodium oxalate-based detergents after "first washing" in the presence of different anionic surfactant (LAS, MES and AES). For cellulase, only sodium oxalate in the presence of LAS has a detergency increase. [ABSTRACT FROM AUTHOR]

A new group of cleavable di-anionic surfactants aliphatic glycerol acetal di-sodium sulfosuccinates has been successfully synthesized starting from esterification reaction of aliphatic glycerol acetals with maleic anhydride, followed by sulfonation with sodium sulfite. The prepared surfactants were characterized by Fourier transform infrared spectroscopy (FT-IR), mass spectroscopy (MS) and elemental analysis. The surface active properties of the new surfactants, such as surface tension, critical micelle concentration (CMC), foaming property, and emulsifying power were determined. [ABSTRACT FROM AUTHOR]

A new layered zirconium phosphate material has been synthesized ionothermally using N-ethylpyridinium (Epy) bromide as both the solvent and the template, and its structure has been solved from synchrotron X- ray powder diffraction data using the charge-flipping routine implemented in Superflip. Rietveld refinement coupled with difference electron density map analysis was used to locate the organic cations between the layers. In the final stages of refinement, it became clear that not only ethylpyridinium but also pyridinium ions were present between the zirconium phosphate layers. These findings were then corroborated using elemental analysis, TGA, and solid-state 13C CP/MAS NMR data. [ABSTRACT FROM AUTHOR]

A new layered zirconium phosphate material has been synthesized ionothermally using N-ethylpyridinium (Epy) bromide as both the solvent and the template, and its structure has been solved from synchrotron X-ray powder diffraction data using the charge-flipping routine implemented in Superflip. Rietveld refinement coupled with difference electron density map analysis was used to locate the organic cations between the layers. In the final stages of refinement, it became clear that not only ethylpyridinium but also pyridinium ions were present between the zirconium phosphate layers. These findings were then corroborated using elemental analysis, TGA, and solid-state 13C CP/MAS NMR data. [ABSTRACT FROM AUTHOR]

By using a large-size amide, dibutylformamide (DBF), as a structure directing agent, a new zeolitic imidazolate framework (ZIF) was synthesized. The ZIF Zn10(Im)20⋅4DBF has an unprecedented zeolitic topology and features 10 crystallographically independent Zn atoms, a 10-membered ring (MR) channel and an unusual 4-connected 10-nodal net. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to describe a more efficient catalyst for the synthesis of lauraldehyde glycerol acetal. Catalytic effect of methane sulfonic acid and p-toluenesulfonic acid were compared. With a mixture of 0.67 wt.% methanesulfonic acid in relation to lauraldehyde, equimolar amounts of glycerol and lauraldehyde being stirred at 110°C for 2.5 h, the yield of the product was 76.32%. When p-toluenesulfonic acid was used, the amount of the catalyst was 0.91 wt.% and the yield of the product was 62.91 % after reacting for 2.5 h at 120°C. The result reveals that methane sulfonic acid is more efficient. Surface tension measurements showed that critical micelle concentration of the product catalyzed by methanesulfonic acid was 5.33 × mol . L-1, and at this point the surface tension could achieve about 24 mN m-1 [ABSTRACT FROM AUTHOR]

We present a novel and convenient method for producing selective stylized simplification of images. The user uses a brush to interactively mark certain areas of the input image which are to be left unaltered. Boundaries of these areas are then automatically optimized to underlying object boundaries in the image. Our method then performs stylized simplification of the unmarked areas, while preserving the marked areas. The method ensures a smooth transition between stylized and unaltered regions to leave a mixed reality image which combines the real and the abstract. Stylized simplification is performed using nonlinear diffusion, which can generate sophisticated results. We modify the classic model of nonlinear diffusion to incorporate bilateral filtering; we apply diffusion speed control of each pixel based on the user's input. The level of simplification can be controlled intuitively based on the diffusion time; another parameter controls the abstraction style, giving a simple and intuitive user interface. Our contributions include a simple-to-use method to produce a novel NPR style and a modified nonlinear diffusion model suited to this selective stylized simplification task. Experimental results show that the final mixed reality results are harmonious. [ABSTRACT FROM AUTHOR]

Two novel zirconium phosphate compounds, l(C9H8N)4(H2O)4I[Zr8P12O40(OH)8F5] and l(C9H8N)2l[Zr2P2O8 (OH)4F4], designated as ZrPOF-Q1 and ZrPOF-Q2, respectively, have been synthesized hydrothermaiy in the presence ot quinoline and HF and characterized by elemental and tharmogravimettc analyses, UV-vis spectroscopy, and scanning electron microscopy. Their crystal structures were determined troni powder X-ray diffraction data using a charge-flipping algorithm. The ZrPOF-Q1 structure [P¯I, a=10.7567(1) A, b = 13.8502(1) Å, c = 14.8995(1) Å, α =109.6(1)°, β=101.1(1 )°, and y=100.5(1)°] consists of zirconium phosphate layers with quinounium ions in between, The layers are unusual in that isolated ZrO2F4 octahedra are anchored on both sides of the layer and protrude into the interlayer space. The ZrPOF-Q2-structure [P¯I, a=7.7058(1) Å, b=12.3547(1) Å, c=6.5851(l) Å, α=97.0(1)°, fin 89.7(1)°, and γ= 101.9(1)°] consists of zirconium phosphate chains with an unusual Zr/P ratio of 1.0, interspersed with quinolinium ions. Both materials are stable up to 250 °C and exhibit Interesting photoluminescence in the UV-vis spectral region. This is attributed to the protonated quinoiine molecules, which are an Integral part of both structures. [ABSTRACT FROM AUTHOR]

Three different kinds of silanols, which include isolated silanol, silanol I (with the hydroxyl proton bonded to an oxygen atom in the adjacent layer) and silanol II (with the hydroxyl proton bonded to the non-bridging oxygen at the same silicon atom), are generated during the hydration process of SKS-6 (δ-Na2Si2O5). 1H–1H nuclear Overhauser enhancement spectroscopy reveals that the proton of silanol I has an effective chemical exchange or spin diffusion with the proton of hydrogen-bonded water, while the proton of silanol II is likely far away from the other proton-containing species. 29Si magic angle spinning, 1H→29Si CP/MAS NMR and 1H–29Si phase-modulated Lee–Goldburg decoupled correlation experiments demonstrate that the local environments of the silicon sites in the final hydrated sample are mainly composed of Q2 [(SiO)2Si(OH)O−Na+], Q3 [(SiO)3Si(OH) and (SiO)3SiO−Na+] and Q4 [Si(OSi)4] groups. [Copyright &y& Elsevier]

Feature is a fundamental design unit in modern solid modeling systems, and this makes a well defined feature interface a matter of concernment in the component-based distributed modeling environment. This paper introduces a feature-based modeling service framework and proposes an interface model of feature-based modeling service toward such a modeling environment, including the support of remote feature attachment and semantic maintenance. A prototype-based feature interface definition strategy using procedural attaching and declarative validation mechanism is discussed in details and how the interface model solves the problems in distributed environment, such as locality-transparent model reusing, is also explained. [ABSTRACT FROM AUTHOR]

The Fischer-Tropsch synthesis can be used to achieve a high content of α-olefin (C5-C11) products using Fe-based catalysts. Herein, C6 and C8 α-olefins have been selected as examples for the alkylation of benzene catalyzed by using an acidic ionic liquid (Et3NHCl-AlCl3) to obtain a variety of intermediates used to prepare surfactants. A series of alkylbenzenes were synthesized by controlling the reaction conditions and their corresponding alkylbenzene sulfonates were successfully obtained by sulfonation and neutralization. It was found that the single chain alkylbenzene sulfonate derivatives did not display typical surfactant properties due to their short hydrophobic chain length. However, double chain alkylbenzene sulfonates exhibit excellent surfactant properties, and decrease the water surface tension compared to commercially available sodium dodecylbenzene sulfonates. A γcmc (mN m-1) value of 32.70 was observed for sodium di-hexylbenzene sulfonates, 29.98 for sodium di-octylbenzene sulfonates, and 36.0 for sodium dodecylbenzene sulfonates. In addition, double chain alkylbenzene sulfonates show an improved emulsifying and wettability performance compared to sodium dodecylbenzene sulfonate. This demonstrates that the capability of alkylbenzene sulfonate to decrease the surface tension are closely related to the total carbon number of side chain-alkyl groups connected to the benzene ring. [ABSTRACT FROM AUTHOR]

Platinum-loaded WO3-Al2O3-SiO2 catalysts, denoted as Pt/WAlSi, in glycerol hydrogenolysis to 1,3-propanediol (1,3-PDO) with a batch reactor were investigated, wherein the WO3-doped silica-alumina material with a homogeneous dispersion was prepared by sol-gel method and Pt was loaded onto it by incipient wetness impregnation. The catalysts were characterized by powder XRD, N2 adsorption-desorption, TEM, CO chemisorption, NH3-TPD, Py-IR, and XPS. The WO3/Al2O3 ratio and Pt loading amount are shown to be of importance in determining the activity and directing the selectivity to 1,3-PDO. It was found that 2% Pt/WAlSi with the ratio of WO3 to Al2O3 at 2 has a suitable Brønsted acidity and contributes to a high selectivity to 1,3-PDO close to 56% at 48% glycerol conversion, and the space time yield for 1,3-PDO in an optimized reaction condition could reach 18.34 g/(gPt h), much higher than the best result reported in the literature. A plausible mechanism of glycerol hydrogenolysis was proposed from the reaction results. [ABSTRACT FROM AUTHOR]

Glycerol, derived from biodiesel production, is a renewable feedstock for the production of value-added chemicals. Herein, we report an investigation of the acetalization of glycerol with n-octanal by homogeneous acid catalysis in the absence of a solvent, using p-dodecylbenzenesulfonic acid, p-toluenesulfonic acid, and sulfuric acid, respectively, as catalysts. p-Dodecylbenzenesulfonic acid, a surfactant-type Brønsted acid, proved to be an excellent catalyst capable of efficiently promoting the reaction under solvent-free conditions, and the yields of glycerol acetals reached 99% under the optimal conditions. The distribution of five- and six-membered cyclic acetal regioisomers varied depending on the reaction time and temperature. Moreover, the amphiphilic properties of the products, with different ratios of five- to six-membered cyclic acetals, have been evaluated by surface tension measurements. [ABSTRACT FROM AUTHOR]

Using bulky amides as the structure-directing agents (SDAs) is an alternative synthetic strategy for the exploration of crystalline large pore (≥12-membered ring) zeolitic imidazolate frameworks (ZIFs). Specifically, by using the bulky amides, dibutylformamide (DBF) and dipropylformamide (DPF) as solvent and imidazole (Im) as a ligand, two ZIFs mimicking the CAN and AlPO-5 (AFI) zeotypes with 12-membered ring (MR) pore openings were synthesized, and denoted as CAN-[Zn(Im)2] and AFI-[Zn(Im)2], respectively. These two materials are the first known examples of Zn(Im)2 polymorphs with 12-MR pores and AFI-[Zn(Im)2] has the largest pore apertures reported to date for ZIF materials. The concept that the bulky amides used were not simply acting as the solvent, but were in fact acting as SDAs or templates during the synthesis of the large pore ZIFs, was suggested by the closeness of the geometrical fit between the guest DBF and the can cages (composite building units) of the CAN-[Zn(Im)2]. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to describe an efficient, easily separable and environmentally friendly glycerin oligomerization catalyst. We explored the catalytic effect of five different layered so-dium silicate materials on the oligomerization reaction of glycerol and compared them with Na2CO3. High performance liq-uid chromatography (HPLC) was used to analyze the product composition. The following reactivity order was observed: δ -Na2Si2O5 ≈ β-Na2Si2O5 ≈ ɑ-Na2Si2O5 > Kanemite > Na-magadiite. δ -Na2Si2O5 showed good selectivity for diglycerol and triglycerol. It was found that 2 wt.% 8-Na2Si2O5 and 5 h at 260°C was the optimal set of reaction conditions. Under these conditions, 71.7% conversion of glycerol was achieved, with selectivity for diglycerol and triglycerol of 83.8%. The results reveal that δ -Na2Si2O5 is an effective catalyst for controlling the degree of poly-merization of glycerol. [ABSTRACT FROM AUTHOR]

The first metal phosphate analogue of the zeolite Na-J (framework type JBW) has been synthesized by an ionothermal approach along with zincophosphate thomsonite. [ABSTRACT FROM AUTHOR]

In this paper, we propose an image semantic model based on the knowledge and criteria in the field of linguistics and taxonomy. Our work bridges the "semantic gap" by seamlessly exploiting the synergy of both visual feature processing and semantic relevance computation in a new way, and provides improved query efficiency and effectiveness for large general image databases. Our main contributions are as follows: We design novel data structures, namely, a Lexical Hierarchy, an Image-Semantic Hierarchy, and a number of Atomic Semantic Domains, to capture the semantics and the features of the database, and to provide the indexing scheme. We present a novel image query algorithm based on the proposed structures. In addition, we propose a novel term expansion mechanism to improve the lexical processing. Our extensive experiments indicate that our proposed techniques are effective in achieving high runtime performance with improved retrieval accuracy. The experiments also show that the proposed method has good scalability. [ABSTRACT FROM AUTHOR]

Catalytic attempts as well as thermodynamic considerations were employed to explore possible measures for enhancing the yield of 1-propanol in propene hydration. The cost of 1-propanol production may be largely reduced if it can be produced from the direct hydration of propene. The thermodynamic considerations suggest that equilibrium distribution of 1- and 2-propanol depends almost solely on reaction temperature; the selectivity of 1-propanol increases linearly with the temperature. Catalytic tests over zeolites HNU-3 and HZSM-5 prove that the reaction behavior is related to the pore structure and surface acidity of zeolites, which could be adjusted through modification with SiCl4or NH4F. Modification of zeolites may suppress the formation of byproduct oligomers, but has only limited improvement on 1-propanol yield. Strong acidity of zeolites is favorable for the hydration to approach the reaction equilibrium, and therefore enhances the selectivity of 1-propanol. [ABSTRACT FROM AUTHOR]

An important aspect of design for the life cycle is assessing the disassemblability of products. This paper presents a novel approach to automatic generation of disassembly sequence from hierarchical attributed liaison graph (HALG) representation of an assembly through recursively decomposing the assembly into subassemblies. In order to increase the planning efficiency, the HALG is built according to the knowledge in engineering, design and demanufacturing domains. In this method, the boundary representation (B-Rep) models are simplified by removing the hidden surfaces to reduce the computational complexity of disassembly planning. For each layer of HALG, the subassembly selection indices defined in terms of mobility, stability, and parallelism are proposed to evaluate the extracted tentative subassemblies and select the preferred subassemblies. To verify the validity and efficiency of the approach, a variety of assemblies including some complicated products are tested, and the corresponding results are presented. [ABSTRACT FROM AUTHOR]