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Surface-enhanced Raman spectroscopy (SERS), having the advantages of high detection sensibility and fast analysis speed, meets the requirements of the detection of sulfur content in simulated gasoline. The optimal preparation conditions of nano-silver substrate which played an important role in enhancing Raman signals was mainly studyed in this paper. Potentiostatic oxidation-reduction method was selected to prepare roughened silver electrode as the nano-substrate. The influences of electrolyte, potential and reduction time were investigated. It shows that bromide ion in electrolytes and nearly balance potential could lead to much better result that relative area intensification factor is equal to 81746.

The microstructure, superhydrophobicity and chemical composition of the moth wing surface were investigated by a scanning electron microscope (SEM), an optical contact angle (CA) meter and a Fourier transform infrared spectrometer (FT-IR). nanosilver film was coated on the wing surface by vacuum evaporation. The wetting mechanism was discussed from the perspective of biological coupling. The moth wing surface, composed of naturally hydrophobic material, is of high hydrophobicity (CA 143~156°) and exhibits complicated hierarchical micro-morphology including primary structure, secondary structure and tertiary structure. The cooperation of hydrophobic material and rough micro-morphology leads to the high hydrophobicity of the wing surface. The wing surfaces coated with 50~1000 nm silver films are still hydrophobic (CA > 110°). The multiple-dimensional rough structure of the wing surface results in the transition of metal silver from hydrophilic to hydrophobic. The moth wing can serve as a bio-template for design and preparation of micro-controllable superhydrophobic surface.

15# nanosilvehas significantly bateriostatic effect against Penicillium, The minimal inhibitory concentrations of 15# nana silve for inhabiting Penicillium is 1 mg/L. Through a comparative study of the bacteriostatic effect of different nanosilver and other bacteriostatic agents against Penicillium, it is found that the bacteriostatic effect of nanosilver against penicillium is very significantly better than lincomycin hydrochloride and streptomycin sulfate, in which, the bacteriostatic effect of nanosilver 14# nanosilve against penicillium is significantly better than 13# nanosilve, and 13# nanosilve is very significantly better than that of 15# nanosilve.It provides a new way for the prevention and control of Penicillium.

A novel method was used to make palygorskite supported nano-silver powder at room temperature. XRD result showed the presence of silver in the final product. TEM investigation revealed that nano-sliver particles of 6-10 nm in diameter were successfully attached on surface of palygorskite fiber. FTIR was also used to clarify the formation mechanism of our method. The antibacterial effect of palygorskite supported nano-silver powder was investigated. Palygorskite supported nano-silver powder had good antibacterial activity on standard Escherichia coli and Staphylococcus aureus.

The bacteriostatic effect of nanosilve is researching purposes. Five strains from Aspergillus was used as the experimented materials. The concentration of nanosilver is180 mg / L. 0.3% carbendazim and 0.3% chlorothalonil was used as compering bacteriostatic agents. The results was gained that nanosilve has inhibiting on the growth, spore’s germination, and effecting on bacteriostasis ring and shape of the Aspergillus. The bacteriostasis of nanosilve is very better than blank comparing experimert. For the bacteriostdsis of nanosilve on Aspergillus, there is differentation among strains. The bacteriostdsis of carbendaim is better than chlorothdonil. The batteriostdsis of chlorothdonil is very better than nanosilve. The bacteriostdsis principle is that nanosilve disrupts permeation of cell membrance of Aspergillus.

Through a comparative study of the bacteriostatic effect of nanosilver of different species and concentrations against bacteria, it is found that nanosilver have significant bacteriostatic effect against bacteria. Bateriostatic effect of nanosilve 15# against B. thuringiensis is significantly better than E.coli, s. aureus and B. subtillis. The optimal concentrations of 15# for inhabiting E. coli, S. aureus, B. subtillis and B. thuringiensis respectively are: 20 mg/L, 10 mg/L, 1 mg/L, 40 mg/L. nanosilvers of 13#, 14# and 15# have no significant differences in the bacteriostatic effect against E.coli, but are all significantly better than the bacteriostats of lincomycin hydrochloride and streptomycin sulfate. Antibacterial principle of nanosilver is damaging the cell membrane permeability.

AgNPs were synthesized by two different methods chemically using sodium citrate as reducing agent, plant mediated by achyranthes aspera as reducing agent. Chitosan (CS) biopolymer is used as a capping agent in order to enhance the stability and dispersibility as well as to remove aggregation. The appearance of surface Plasmon band in the ultraviolet-visible spectra (410-445 nm) is due to the formation of AgNPs in different sizes. Also the data was clarified that the CS molecules coordinate to the surface of nanoAg particles through their head-groups. FTIR spectra were recorded in a Perkin Elmer version 10.03.06, Spectro Photometer. The FTIR analysis suggests that the prepared chitosan silver nanocomposite film consists of an intermediate/or complex of tri-ammonium citrate, chitosan and metal ions. Finally Antibacterial activity of Ag-CS composites indicating that highest antibacterial activity was detected with green film than chemical film.

A novel electrode has been fabricated with electroabsorbing hemoglobin on the nanosilver coated carbon nanotubes modified glassy carbon electrode (Hb/Ag/CNT/GC). The modifed electrodes showed an excellent electrocatalytic activity for reduction of dissolved oxygen. The peak current is linear with oxygen concentration in the range from 1.63×10-6to 2.58×10-4mol.L-1with a calculated detection limit of 9.78×10-7mol.L-1at a signal-to-noise rate of 3, the linear regression equation is i=0.0478C+0.0331 (R2=0.994; i: μA; C: the concentration of oxygen, μmol.L-1). So, the developed electrode was used to determination of oxygen in the water and actual samples and satisfactory results were obtained. The Hb/Ag/CNTs composites may be a potential cathode material of the air battery.

Silver nanoparticles have been prepared using reductive polysaccharides (glucan) as protecting agents and silver nitrate as precursor via a facile green approach, and possible formation mechanism of silver nanoparticle was proposed in this paper. Silver nanoparticles appearance, size and size distribution were controlled by different synthesis technologies and reaction conditions. By changing the reaction conditions such as AgNO3 solution concentration, glucan dosage, reaction temperature, reaction time, the parameters affecting the product shape, particle size and size distribution were investigated. The samples synthesized were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-vis spectrophotometer (UV-vis) methods. The results have showed that nanosilver particle with different shapes such as rod-like, sheet-like or flake and tree-like etc. can be prepared by reductive polysaccharides, and it is a green preparation technology.

Based on our previous work of MSA influence on silver nano particles formation we have performed a series of research related to the preparation and characterization of silver nanoparticles which synthesized through coprecipitation process. The silver nano particles was transformed into silver nanoparticles films by spin coating deposition method. The silver nanoparticles were prepared from silver acetate as precursor, reductant agent phenylhydrazine, and dodecylamine as stabilizer. X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Analysis (EDAX), and Electric Four Point Probe have been used to characterize the silver nanoparticles as well as the films. The morphology and the crystal structure have been determined by means of XRD and SEM. The average grain size of silver nanoparticles is found to be 22 nm. The peaks in XRD pattern are in good agreement with that of face-centered-cubic phase of metallic silver. The electrical conductivity films were confirmed in the range of conducting material. The highest conductivity was reached at 3,88 x 109 S/cm associated to 1600 rpm of spin coater rotation.

In this work, we use 3D finite difference time domain (3D-FDTD) to calculate the plasmon resonance effect for a single silver hemisphere in which the palsmon line shape have distinct peaks when the particles are located on a glass substrate. The dependence of the resonance on hemisphere size and the ratio of height over radius are characterized, and it is found that the surface interface effect played an important role on the plasman resonace effect for a single silver hemisphere.

The use of nanoparticles has spannded many divisions of biological fields including sensors, drug delivery and clinical diagnosis. These functions all based on the most important action in cells called Endocytosis. The study of endocytosis in higher order plants remained inactive for a long period of time. In this work we use Silver Nano Particles (S.N.Ps) as a endocytosic substances were incubated by isolated protoplast of petunia .Concurrently, with the study of internalization, their appear aggregation inter and intracellular were investigated by Transmissions Electron Microscopy (TEM). Results and observations showed that the S.N.Ps crossed the cell membrane and internalized in to the cells. It can be assumed that the particles with the organic functionality – PEG coated – were internalized by the petunia protoplasts.

CeO2 nanobundles were obtained by the microwave homogeneous precipitation method using cerium nitrate and urea as raw materials. Ag nanoparticles were obtained by the microwave solvolthermal method using silver nitrate, PVP and ethanol as raw materials. Nanostructured Ag/CeO2 was prepared by the impregnation method. The products were characterized by X-ray diffraction, SEM, TEM, UV-vis spectrum, BET. The photocatalytic properties of CeO2 and Ag/CeO2 nanomaterials were evaluated by degradation of methyl orange. The results show that the photocatalytic degradation of modified cerium oxide modified by nano silver on methyl orange is significantly improved. For the Ag (0.1 wt%)/CeO2 material, the degradation rate on methyl orange is up to 83.2% under visible light irradiation for 1h. The catalytic activity of nanostructured Ag (0.1 wt%)/CeO2 in dye decolorization is substantially higher than the standard reference TiO2 P25.

Normal grain growth of silver thin film predominates above the critical transition temperature below which bimodal grain growth predominates. In this experiment silver Nano layers were prepared by spin coating on glass substrate and which were annealed at different temperature. The lowest attainable resistance was 1.23 Ohm/sq. The woulf plot of fcc silver suggests that during growth (111) family plane predominated on surface of every grain and that was true according to SEM figure. This is the reason for low resistivity of silver thin film. Not only on surface but also this stable (111) plane was present on grain boundary as singular interface. However, ADF Simulation has been done to construct 40 nm silver nano particle and to construct band structure of silver. The valance band and conduction band overlap shows the metallic characteristic property of silver.

It has many advantages with liquid phase reduction method to prepare the nano-silver, such as experimental conditions are simple, low cost, energy-saving, etc.. At the same time, the nano silver powder prepared by this method has high surface activity, catalytic property and wide usage. In this paper, nano-silver powder was prepared by changing the amount of protective agents with chemical liquid phase reduction method. This paper focuses on the impact of the amount of protective agent on the nano-silver. In addition, we also analyzed the reaction temperature, PH value of solution, viscosity and electrical conductivity on the preparation of nano-silver. Finally, test results from the TEM shows that the nano-silver was prepared with smaller size, uniform size and good dispersion.

In this study, the nano-silver impregnated media (NAg-ball) was proposed to inactive E. coli in water. After 24 h of contact with NAg-ball, about 99 % removal of E. coli from the water sample with an initial bacteria loading oItalic textf 103 - 105 CFU/ml was observed. According 32 day repetitive use, periodical surface cleaning would be suggested to maintain the high inactivation lasting of NAg-ball. The dosing of 1: 20 (Nag-ball: water) was found to be the best and most suitable in a 500 L pilot scale. This result confirmed the existence of synergistic effect lower dose shall be expected to treat the same loading of bacteria for further larger scale. Toxicity Characteristic Leaching Procedure (TCLP) test revealed trace amount of Ag, Cu, Cr and Zn released from NAg-ball into the treated water sample. In conclusion, nano-silver impregnated media has very good inactivation performance on E. coli. This NAg-ball provides a safe, convenient and effective solution in drinking water treatment, especially in the mountain area.

Conductive ink, especially the nano-silver ink is becoming more and more popular in printable electronic field. In order to synthesize high concentration, stable nano-silver colloid, liquid chemical reduction is used and different ratios of PVP to silver nitrate are studied. After precise adjustments of the parameters, colloid with silver content of wt7.8% is obtained. Particle size distribution, UV-Vis spectra, thermo gravimetric analysis and SEM images are conducted to characterize the silver particles. The results show that when molar ratio of PVP to silver nitrate is 0.6, the average particle size is 170nm and some deposit can be seen, while the ratio increases to 1.5, the size decreases to 68nm, and the residue quality of the silver colloid showed in the TG analysis is 7.88%. After aging for 1 month, the colloid is still stable and the color keeps to the original dark green. When the ratio continues increasing to 2.5, particle size becomes 112nm and some larger particles beyond 3μm can be observed.

A paste with as low as 300°C sintering temperature was prepared by using nano silver particles and nitrocellulose ethyl acetate solution. The rheological and thixotropic behaviors of the typical paste were characterized and their effects on the screen printing ability were analyzed in details. The paste demonstrates a typical shear thinning rheological behavior and thixotropic of pseudoplastic fluid. The apparent viscosity decreased rapidly with the increase of the shear rate. The paste is proper for the manufacturing electrical components at a low sintering temperature as low as 300°C.

This article will present using chemical reduction to prepare silver nano-particles, which is a certain improvement base on the traditional hydrogen peroxide (H2O2) Silver ammonia by using a new reductant urea peroxide (CO (NH2) 2•H2O2) to replace hydrogen peroxide. Hydrogen Peroxide silver ammonia is widely used in the nano-silver particles Preparation, however, the nano-silver particles prepared in traditional ways is not homogeneous and very easy agglomerated, therefore, in this experimental by using of urea peroxide as a reductant, under condition of temperature 30°C, 45 nm homogeneous nano-silver particles is successfully prepared. The detection instrument used in the experimental is transmission electron microscopy and laser particle size analyzer.

Three different chemical reductions are used to synthesize spherical silver particles with different sizes. The results show that the sizes of silver particles by glucose、HCOONH4 and NaBH4 reduction are 49nm, 187nm and 37nm and those silver particles with the size below 100nm by HCOONH4 and NaBH4 reduction have narrow size distributions of 30-70nm. In addition, it has been found that adding a small amount of silver nano-particle can improve the conductivity of that whose size surpasses 100nm which is beneficial to the increase of efficiency of the solar cell when adding it into the silver electronic paste.

All-printed electronics as a mean of fast processing and achieving ultra-low-cost electronic devices has attracted great interest in recent years. Inkjet printing has excelled as the most promising technique by which the circuit components can be directly drawn on the specific area in one step. Furthermore, the low temperature reduction processes can be achieved by exploit the low-melting point characteristic of nanometallic particles. The inkjet printing technique to deposit silver nanoparticles (3.39±1.21 nm) capped by saturated 3-Mercaptopropionic acid onto silicon substrate was studied. The silver patterns were tested for its functionality as circuit components like conductor, resistor and capacitor. All components can be produced simply by thermal annealing of an inkjet printed patterns under an atmosphere of 90% N2-10% H2 at 300°C for 1 hr.

Compared with traditional etch processing, inkjet technology has the features of simpler workmanship, less resources-utilizing, lower cost and environmentally friendly adaptation, which is sure to be another innovation of printed circuit board(PCB) technology. In this paper, size and shape controlled silver nanoparticles have been synthesized，which was used as conductive medium in ink-jet inks. Then it was printed into conductive lines on epoxy resin by a drop-on-demand inkjet printer. PVP was used as a polymeric stabilizer providing both electrostatic and steric stabilization. Ag2C2O4 was used to prepared spherical nano-silver. In the preparation of flake-like silver powders, the fully inorganic phase system contains AgNO3 as a silver precursor, DMF as a as a media dissolving silver salt, and PVP as a reducing reagent. The morphologies and structures of the nanoparticles were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was shown that the sample is silver with cubic asymmetry from the pattern of XRD. TEM images indicated that the size of spherical nano-particles was no more than 20 nm. But the small triangular nanoplates, with rather narrow size distribution, were in the range from 20nm up to 60 nm in edge length. The electrical conductivity was also measured by the four-probe tested method after calcined on the substrates. It was shown that the conductivity was 25S/cm when adding the spherical powders and the nano-silver ink has been successfully designed for inkjet printing.

A paste with as low as 300°C sintering temperature was prepared by using nano silver particles and ethyl cellulose solution. The rheological and thixotropic behaviors of the typical paste were characterized and their effects on the screen printing ability were analyzed in details. The paste demonstrates a typical shear thinning rheological behavior and thixotropic of pseudoplastic fluid. The apparent viscosity decreased rapidly with the increase of the shear rate. The paste is proper for the manufacturing electrical components at a low temperature as low as 300°C.

In order to improve the antibacterial property of silk fabric, nano-silver was used to deal with the silk fabric by steaming in the light of in-situ methanism. All of the factors which affect the content of nanosilver and the whiteness of the finished silk were studied. These factors are the concentration of RSD solution, the concentration of silver nitrate solution, the steaming temperature and the dipping time. The optimum technology obtained was showed as follows: the silk fabric should be treated with the concentration of 2g/L RSD and the concentration of 0.085g/L silver nitrate, and steamed for 30 minutes after dipped for 5 minutes. The results of the inhibition zone test and the antibacterial rate test indicated that both the silk fabric finished by the optimum technology and the one settled by five times diluted optimum technology showed highly antibacterial property. Even if the solutions are diluted by 5 times, the antibacterial rate of finished fabric is up to 99.67% to Staphylococcus aureus and 99.99% to Escherichia coli. Meanwhile, the inhibition zone is 7.9mm to Staphylococcus aureus and 8.3mm to Escherichia coli. In addition, the whiteness of the finished fabric was changed a little.

Polyaniline was synthesized by the chemical synthesis. Polyaniline as dispersion agent, nano silver / polyaniline composite particles was prepared by In-situ Synthesis in DMF solution. Nano Silver / Polyaniline / PMMA composites were prepared by direct dispersion method. The microstructure and characterization of the sample were studied by UV-Vis absorption spectroscopy infrared spectroscopy and XRD. The composite electrical conductivity was measured by four-probe method, showing that nano silver / polyaniline composite particle size was about 31.0 nm. When the doping concentration of nano-silver reached 0.12%, the electrical conductivity of silver / polyaniline / PMMA composite comparing to the pure PMMA material increased four orders of magnitude.

The hydroxyl in polysaccharide and flavones that extracted from Artemisia argyi can absorb onto the surface of silver nanoparticles and prevent aggregation from nanoparticles. The stable nano-silver solution was got. The preparation of Nano-silver Artemisia Argyi by Artemisia Argyi extract in alkaline and acidic environment was investigated, and the antibacterial property of fabric finished by the nano-silver Artemisia Argyi was analyzed. The experimental results show that the silver nanoparticles prepared in alkaline environment has small size with the minimum 12nm and uniform dispersion. The fabric finished by Nano-silver Artemisia Argyi exhibited strong antibacterial activity against E.coli and S.aureus, the sterilized rate was over 99.9%. The fabric has excellent antibacterial washability too.

Printing electronics technology promotes the application of conductive ink. In this paper, the manufacture of nano-sliver conductive ink is investigated. First, Spherical silver nano-particles were reduced from silver nitrate solution by liquid chemical reduction method, with hydrazine hydrate as reductant and PVP as surface-protection reagent. SEM was used to characterize the morphology of silver powders, and the mean particles size is 62.79 nm. Then, conductive ink was prepared with nano-silver particles made in this research as conductive fillers, polyurethane resin and acrylic resin as binders, and stearic acid as dispersant. In the last, the conductive ink was printed on the PCB substrate by screening printing. After the ink is dried, conductivity, abrasion resistance, and adhesion were tested. The experiment results shows that the order of sheet resistivity magnitude is 10-4Ω•m, the number of rubbing fastness is more than 6000, and the adhesion can be resisted repeatedly to tape tear.

Stable nano-silver colloids with highly pure silver were synthesized by using polyethylene glycol as solvent, stabilizer and reducing agent. The colloidal nanoparticles need not be separated from the solution and the silver sol can be directly used in antibacterial fields. Tannic acid and ascorbic acid were used as co-reducing agents to improve conversion rate of silver ion. Transmission electron microscopy (TEM) analysis showed that stable spherical metal particles 3-50 nm in diameter with a well-crystallized structure were obtained by using tannic acid as co-reducing agent,15-20 nm in diameter were obtained by using ascorbic acid as co-reducing agent. The X-ray diffraction (XRD) study revealed the formation of metallic silver particles crystallized in the face centered cubic (fcc) structure. The antimicrobial test results illustrated that the nano-silver colloids have excellent antimicrobial effects against E.coli and Streptomyces.

Nano size silver films were deposited on the surface of regenerated cellulose films by magnetron sputtering, to impart antibacterial functionality to the cellulose films. Field emission scanning electron microscopy (FESEM) images revealed that the silver films were composed of nano size compact grains and the surface shape of the grains changed with changing sputtering power. As the power increased, the size of the nano silver grains increased and the number of grains decreased. Surface elemental analysis by energy dispersive spectrometry (EDS) showed a small amount of elemental silver on the surface. The antibacterial activity of the films was assessed by the shake flask test which measured the number of Staphylococcus aureus bacteria. The percentage reduction of the bacteria reached >99.9%.

In this paper, A kind of ideal non-cyanide silver deposits was obtained by joining the ultrasonic. ultrasonic frequency of 28KHz, power increased from 0-500W, XRD tests show:with the increasing in electric power deposition, silver coating (111) and (200) crystal plane orientation significantly improved, and (220) crystal plane orientation declined . With the ultrasonic power increased, silver deposition current efficiency increased first and then reduced. the grain size refined with the ultrasonic increasing .the corrosion resistance decreased with the ultrasonic increasing.and SEM showed that the grain sizes decreased with the ultrasonic.

Poly-L-Lactide (PLLA) composites were prepared with nano silver particles with the weight ratios of nano silver particles to PLLA (Ag/PLLA) at 0.5%, 2.5%, 5%, 7.5% and 10% (w/w). In vitro cytotoxicity tests were conducted firstly to evaluate the cytotoxicity of the composites. The results indicated that PLLA, 0.5%, 2.5% and 5% Ag/PLLA composites were nontoxic to cells, while 7.5% and 10% Ag/PLLA composites were significantly toxic to cells. Cell proliferation experiments and antibacterial tests were also performed. 5% Ag/PLLA was found the best for cell proliferation with obvious antibacterial property. Thus, Ag/PLLA can be used as nontoxic scaffolds for tissue engineering with antibacterial property.