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1.
Appl Opt ; 61(10): 2750-2756, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35471347

RESUMO

Fringe projection profilometry is a high-precision method used to measure the 3D shape of an object by projecting sinusoidal fringes onto an object. However, fringes projected onto a metallic or shiny object are distorted nonlinearly, which causes significant measurement errors. A high-precision measurement method for shiny objects that employs computer graphics (CG) and deep learning is proposed. We trained a deep neural network by projecting fringes on a shiny object in CG space. Our results show that the method can reduce the nonlinear fringe distortion caused by gloss in real space.

2.
Artigo em Inglês | MEDLINE | ID: mdl-22259554

RESUMO

The asymmetric unit of the title compound, C(9)H(4)S(7), contains two independent mol-ecules, in one of which the central five-membered ring is disordered over two orientations in a 0.924 (3):0.076 (3) ratio. The mol-ecular skeleton is almost planar: the average distance of the atoms from their mean plane is 0.128 (7) Šin the ordered mol-ecule, and 0.088 (5) and 0.123 (2) Šin the major and minor disorder components, respectively. The ordered and disordered mol-ecules form separate columns by stacking along the b axis. Adjacent columns inter-act via short S⋯S [3.33 (2), 3.434 (3), 3.444 (2), 3.503 (2), 3.519 (3) and 3.53 (4) Å] and S⋯H [2.814 (2), 2.87 (7), 2.92 (2), 2.9269 (18), 2.93 (2), 2.94 (2), 2.939 (2), 2.967 (2) and 2.974 (1) Å] contacts.

3.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 11): o2716, 2009 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-21578314

RESUMO

The mol-ecular framework of the title compound, C(11)H(6)I(2)OS(8), is almost planar [maximum deviation = 0.057 (5) Å] except for the two methyl-sulfanyl groups, which are twisted relative to the mol-ecular skeleton, with C-C-S-C torsion angles of 49.74 (22) and 82.91 (21)°. In the crystal, mol-ecules are stacked alternately in opposite orientations, forming a one-dimensional column along the b axis. The inter-action between adjacent columns is accomplished through S⋯S [3.4289 (5) Å], S⋯I [3.4498 (4) Å] and O⋯I [2.812 (2) Å] contacts.

4.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 11): o2831, 2009 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-21578421

RESUMO

The mol-ecular skeleton of the title mol-ecule, C(11)H(6)I(2)S(9), is nearly planar [maximum deviation 0.052 (3) Å] except for the two methyl groups. In the crystal, mol-ecules related by translation along b axis are associated into columns through π-π inter-actions between the five-membered rings, with a centroid-centroid distance of 3.593 (5) Å. Inter-action between adjacent columns is accomplished by short S⋯I contacts of 3.2099 (4) Å.

5.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 11): o2920, 2009 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-21578498

RESUMO

The mol-ecular framework of the title compound, C(11)H(7)IOS(8), is almost planar [maximum deviation = 0.040 (4) Å], except for the two methyl-sulfanyl groups, which are twisted relative to the mol-ecular skeleton, making C-S-C-C torsion angles of 144.1 (8) and -141.3 (8)°. In the crystal, mol-ecules are stacked alternately in opposite orientations, forming a one-dimensional column parallel to [110]. The primary inter-actions between mol-ecules comprising the columns are of the S⋯S type [3.554 (1) Å]. Inter-actions between columns are of the S⋯S type [3.411 (1) along b and 3.444 (1) Šalong c], as well as S⋯I contacts [3.435 (2) Å].

6.
Chemosphere ; 69(3): 493-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17509657

RESUMO

Some unavoidable drawbacks of traditional technologies have made phytoremediation a promising alternative for removal of arsenic from contaminated soil and water. In the present study, the potential of an aquatic macrophyte Spirodela polyrhiza L. for phytofiltration of arsenic, and the mechanism of the arsenic uptake were investigated. The S. polyrhiza L. were grown in three test concentrations of arsenate and dimethylarsinic acid (DMAA) (i.e. 1.0, 2.0 and 4.0microM) with 0 (control), 100 or 500microM of phosphate. One control treatment was also set for each test concentrations of arsenic. The PO(4)(3-) concentration in control treatment was 0.02microM. When S. polyrhiza L. was cultivated hydroponically for 6d in culture solution containing 0.02microM phosphate and 4.0microM arsenate or DMAA, the arsenic uptake was 0.353+/-0.003micromolg(-1) and 7.65+/-0.27nmolg(-1), respectively. Arsenic uptake into S. polyrhiza L. was negatively (p<0.05) correlated with phosphate uptake when arsenate was applied to the culture solutions owing to similar in the sorption mechanism between AsO(4)(3-) and PO(4)(3-), and positively (p<0.05) correlated with iron uptake due to adsorption of AsO(4)(3-) onto iron oxides. Thus, the S. polyrhiza L. accumulates arsenic by physico-chemical adsorption and via the phosphate uptake pathway when arsenate was added to the solutions. These results indicate that S. polyrhiza L. would be a good arsenic phytofiltrator. In contrast, DMAA accumulation into S. polyrhiza L. was neither affected by the phosphate concentration in the culture nor correlated (p>0.05) with iron accumulation in plant tissues, which indicates that S. polyrhiza L. uses different mechanisms for DMAA uptake.


Assuntos
Arsênio/metabolismo , Clorófitas/metabolismo , Plantas/metabolismo , Poluentes Químicos da Água/metabolismo , Oxirredução
7.
J Hazard Mater ; 146(1-2): 39-50, 2007 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-17184914

RESUMO

Crosslinked chitosan resin chemically modified with L-lysine has been used to investigate the adsorption of Pt(IV), Pd(II) and Au(III) from aqueous solutions. Batch adsorption studies were carried out with various parameters, such as initial metal ion concentration, contact time, pH and temperature. The maximum adsorption capacity was found at pH 1.0 for Pt(IV), at pH 2.0 for Au(III) and Pd(II). Langmuir and Freundlich isotherm models were applied to analyze the experimental data. The best interpretation for the experimental data was given by the Langmuir isotherm and the maximum adsorption capacity was found to be 129.26 mg/g for Pt(IV), 109.47 mg/g for Pd(II) and 70.34 mg/g for Au(III). The kinetic data was tested using pseudo-first-order and pseudo-second-order kinetic models. Kinetic data correlated well with the pseudo-second-order kinetic model, indicating that the chemical sorption was the rate-limiting step. Thermodynamic parameters like Gibbs free energy (DeltaG degrees), enthalpy (DeltaH degrees) and entropy (DeltaS degrees) were evaluated by applying the Van't Hoff equation. The thermodynamic study indicated that the adsorption process is spontaneous and exothermic in nature. The desorption studies were carried out using various reagents. The maximum percent desorption of precious metal ions were obtained when the reagent 0.7 M thiourea-2 M HCl was used.


Assuntos
Ouro/química , Paládio/química , Platina/química , Poluentes Químicos da Água/química , Adsorção , Quitosana , Concentração de Íons de Hidrogênio , Lisina/análogos & derivados , Soluções , Temperatura , Purificação da Água/métodos
8.
Anal Sci ; 21(12): 1553-6, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16379406

RESUMO

Phytoremediation is an innovative technology that utilizes the natural properties of plants to remediate hazardous waste sites. For more cost-effective phytoremediation, it is important to utilize a hyperaccumulating plant after phytoremediation, i.e. the recovery of valuable metals and the production of useful materials. In this work, the determination of metals in plant component polymers in a fern, Athyrium yokoscense, as a hyper-accumulating plant was established using steam explosion, Wayman's extraction method, and ICP emission spectrometry. After A. yokoscense plants were treated by steam explosion, the steam-exploded A. yokoscense were separated into four plant component polymers, ie. water-soluble material fraction, holocellulose fraction, methanol-soluble lignin fraction, and residual lignin fraction. The concentrations of Cu, Pb, Fe, and Zn in these plant component polymers and the dry weights of plant component polymers were measured. These analytical process determining metals in the plants will contribute to not only the evaluation and the efforts of phytoremediation using a hyperaccumulating plant, but also to the development of more effective phytoremediation.


Assuntos
Biopolímeros/química , Cobre/análise , Gleiquênias/química , Ferro/análise , Chumbo/análise , Zinco/análise , Análise Espectral/métodos
9.
Anal Sci ; 20(1): 61-8, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14753258

RESUMO

A new monitoring system for bacterial communities involving dimethylarsinic acid (DMAA) decomposition was provided by combining the MPN (Most Probable Number) method and RFLP (restriction-fragment-length polymorphism analysis). The abundance of DMAA decomposing bacteria was estimated by the MPN method using a bacterial culture medium, which included DMAA as the sole carbon source, indicating bacterial cell densities of 1700 cells/ml in Lake Kahokugata and 330 cells/ml in Lake Kibagata. After isolating the dominant bacteria using agar plates, the isolates were classified into some genotype groups by RFLP analysis using 16S rDNA sequences. Classification of the RFLP analysis indicated that 14 isolates of Lake Kahokugata were classified into 6 types, which included 2 dominant types related to genus Pseudomonas, while 8 isolates of Lake Kibagata displayed 6 types including one or two isolates. Moreover, the RFLP types were unique for each lake, suggesting that DMAA decomposing bacteria were specific for the aquatic environment related to the arsenic cycle. The activities of DMAA decomposition mostly matched with the RFLP type category of the isolates. Accordingly, combining the MPN method with the RFLP analysis will play an important role in elucidating the distributions and dynamics of the DMAA-decomposing bacterial community.


Assuntos
Bactérias/metabolismo , Ácido Cacodílico/metabolismo , RNA Ribossômico 16S/genética , Bactérias/genética , Biodegradação Ambiental , Polimorfismo de Fragmento de Restrição , Microbiologia da Água
10.
Anal Sci ; 20(1): 89-93, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14753263

RESUMO

The sample preparation and analytical methodology are described for detecting biologically produced iron(III)-binding ligands in laboratory cultures of coastal marine phytoplankton. The iron(III)-binding ligands from the culture media were purified by passage through a column packing with a hydrophobic absorbent. The concentrations and stability constants of the ligands were determined by adsorptive cathodic stripping voltammetry with competitive ligand equilibration. The analytical results of the cultivated cultures suggest that eukaryotic phytoplankton would produce iron(III)-binding ligands in analogy with other microorganisms.


Assuntos
Eletroquímica/métodos , Ferro/metabolismo , Fitoplâncton/metabolismo , Eletrodos , Ligantes , Biologia Marinha
11.
Inorg Chem ; 41(18): 4763-9, 2002 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-12206702

RESUMO

The 2:1 charge-transfer (CT) salts (1(2).FeBr(4) and 1(2).GaBr(4)) of ethylenedithiotetrathiafulvalenoquinone-1,3-dithiolemethide (1) with FeBr(4)(-) and GaBr(4)(-) counteranions were obtained as needle crystals, whose structures are almost the same as each other. The 1 molecules form a one dimensionally stacked column with alternation of their molecular axis direction, while the counteranions are aligned in parallel with the 1-stacked columns with the direction of their distorted-tetrahedral geometry maintained. The room-temperature electrical conductivities measured on the single crystals of 1(2).FeBr(4) and 1(2).GaBr(4) were 4.6 and 2.1 S cm(-1), respectively. From the temperature dependences of their electrical conductivities in both cases the electrical conducting properties were metallic between ca. 170 and 300 K, but below ca. 170 K converted to be semiconducting and continued till 5 K, although the activation energies are very small (4-10 meV). For 1(2).FeBr(4) very weak and antiferromagnetic interaction occurred between the d spins of FeBr(4)(-) ions in the temperature range of ca. 1-300 K. However, below ca. 15 K the ferromagnetic interaction was reversely preferential possibly by participation of the pi spin of 1.

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