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This study evaluates the antibacterial and antifungal effects of ethanol extracts from Gnaphalium uliginosum L. derived from freshly harvested plant biomass, including stems, leaves, flowers, and roots. The extract was analyzed using gas chromatography-mass spectrometry (GC-MS) to determine its antimicrobial activity against phytopathogenic bacteria and fungi. Two methods were used in the experiments: agar well diffusion and double serial dilution. Extraction was carried out using the maceration method with different temperature regimes (25 °C, 45 °C, and 75 °C) and the ultrasonic method at various powers (63–352 W) for different durations (5 and 10 min). It was found that the 70% ethanol extract obtained through the ultrasonic experiment at 189 W power for 10 min and at 252 W power for 5 min had the highest antimicrobial activity compared to the maceration method. The most sensitive components of the extracts were the Gram-positive phytopathogenic bacteria Clavibacter michiganensis and the Gram-negative phytopathogenic bacteria Erwinia carotovora spp., with MIC values of 156 μg/mL. Among the fungi, the most sensitive were Rhizoctonia solani and Alternaria solani (MIC values in the range of 78–156 µg/mL). The evaluation of the antimicrobial activity of extracts using the diffusion method established the presence of a growth suppression zone in the case of C. michiganensis (15–17 mm for flowers, leaves, and total biomass), which corresponds to the average level of antimicrobial activity. These findings suggest that G. uliginosum has potential as a source of biologically active compounds for agricultural use, particularly for developing novel biopesticides. [ABSTRACT FROM AUTHOR]

This study evaluates the antibacterial and antifungal effects of ethanol extracts from Gnaphalium uliginosum L. derived from freshly harvested plant biomass, including stems, leaves, flowers, and roots. The extract was analyzed using gas chromatography-mass spectrometry (GC-MS) to determine its antimicrobial activity against phytopathogenic bacteria and fungi. Two methods were used in the experiments: agar well diffusion and double serial dilution. Extraction was carried out using the maceration method with different temperature regimes (25 °C, 45 °C, and 75 °C) and the ultrasonic method at various powers (63–352 W) for different durations (5 and 10 min). It was found that the 70% ethanol extract obtained through the ultrasonic experiment at 189 W power for 10 min and at 252 W power for 5 min had the highest antimicrobial activity compared to the maceration method. The most sensitive components of the extracts were the Gram-positive phytopathogenic bacteria Clavibacter michiganensis and the Gram-negative phytopathogenic bacteria Erwinia carotovora spp., with MIC values of 156 μg/mL. Among the fungi, the most sensitive were Rhizoctonia solani and Alternaria solani (MIC values in the range of 78–156 µg/mL). The evaluation of the antimicrobial activity of extracts using the diffusion method established the presence of a growth suppression zone in the case of C. michiganensis (15–17 mm for flowers, leaves, and total biomass), which corresponds to the average level of antimicrobial activity. These findings suggest that G. uliginosum has potential as a source of biologically active compounds for agricultural use, particularly for developing novel biopesticides.

Aim: To evaluate the antibacterial activity of a-mangostin compounds against Prevotella intermedia bacteria using the diffusion method. Material and Methods: This type of research is a prospective analysis and in vivo experimental laboratory study. Research on a-mangostin as an antibacterial to inhibit the growth of the P. intermedia bacteria type (ATCC25611) with catalog number R3602016 was produced by Thermo Scientific, Inc. US. Fifty P. intermedia culture samples were chosen at random technique. The diffusion method is then used to assess the antibacterial activity of the a-mangostin compounds. Statistical Analysis: The data obtained were then examined using statistical assessment using the Kruskall-Wallis tests. Results: The results showed a concentration of a-mangostin which produces a zone of inhibition of the growth of P. intermedia with a diameter approaching the positive control group is the concentration of a-mangostin 100% then 50%, 25%, and 12.5%. Meanwhile, the concentration of a-mangostin which resulted in a zone of inhibition of the growth of P. intermedia bacteria with the same diameter as the negative control group was a-mangostin concentrations of 6.25%, 3.125%, 1.56%, and 0.78%. Conclusion: The a-mangostin compound has effective activity against the growth of the P. intermedia bacteria. [ABSTRACT FROM AUTHOR]

Ariana Kameri,1 Arben Haziri,2 Zeqir Hashani,3 Agime Dragidella,1 Kemajl Kurteshi,4 Arsim Kurti5 1Department of Dental Pathology and Endodontics, University of Prishtina “Hasan Prishtina”, Faculty of Medicine, Prishtina, Kosova; 2Department of Chemistry, Natural Science Faculty, University of Prishtina “Hasan Prishtina”, Prishtina, Kosova; 3Education Faculty, University of Prizren “Ukshin Hoti”, Prizren, Kosova; 4Department of Biology, Natural Science Faculty, University of Prishtina “Hasan Prishtina”, Prishtina, Kosova; 5Department of Microbiology, Medical Faculty, University of Prishtina “Hasan Prishtina”, Prishtina, KosovaCorrespondence: Agime Dragidella, Department of Dental Pathology and Endodontics, University of Prishtina “Hasan Prishtina”, Faculty of Medicine, Rrethi i spitalit, p.n, Prishtina, 10000, Kosova, Tel +383 44 130 674, Fax +383 38 512 525, Email agime.dragidella@uni-pr.eduPurpose: With the demand for better efficiency during endodontic therapy, the purpose of this in vitro study was to evaluate the efficiency of ethyl acetate (EthOAc) extract of Matricaria chamomilla (L.) against Enterococcus faecalis and compare with standard root canal irrigation solutions.Material and Methods: The antibacterial effect against Enterococcus faecalis of the EthOAc extract of Matricaria chamomilla was assessed without, or with dentine powder, using agar disk diffusion method. The inhibition zones induced by the EthOAc extract were observed after 5 minutes, 60 minutes, and 24 hours and compared with standard irrigation solutions (2% chlorhexidine and 2% sodium hypochlorite) without, or after mixing with dentine powder. Statistical analysis of the results were analysed with the Kruskal–Wallis test and one-way ANOVA.Results: There was no inhibition zone in samples with and without dentine powder after combination of ethyl acetate extract of Matricaria chamomilla with sodium hypochlorite. When the extract was used alone in samples without dentine powder, the inhibition zone was 9.7 mm after 24 h, but this zone was decreased after adding dentine powder (7.7 mm). When the extract was used in combination with CHX, the inhibition zone in samples with dentine powder was 25.3 mm, but it was decreased after adding dentine powder (21.7 mm).Conclusion: The EthOAc extract of Matricaria chamomilla as alternative root canal irrigant may be a useful natural agent with antibacterial activity against Enterococcus faecalis. Also, it showed promising results in endodontic therapy after combination with chlorhexidine in Enterococcus faecalis eradication.Keywords: root canal, herbal plants, diffusion method, chlorhexidine, sodium hypochlorite

Bioactive chemicals are abundant in natural products; some have strong antibacterial properties. Coriander (Coriandrum sativum. Linn) is one of the spices with a long history of use in traditional medicine and foods. Apart from its use as a flavouring agent in foods, it also has a wide range of applications in man's healthcare due to its numerous phytoconstituents, with notable antibacterial activities. This review summarizes the findings of scientific studies on the antimicrobial activity of Coriander, highlights the methods used for testing the antimicrobial activity, the part(s) of the plant used, and the compounds of Coriander with antimicrobial activity. This review concludes that Coriander is a source of therapeutic agents for infectious diseases and food-borne pathogens. [ABSTRACT FROM AUTHOR]

Digital images can be easily shared or stored using different imaging devices, storage tools, and computer networks or wireless communication systems. However, these digital images, such as headshots or medical images, may contain private information. Hence, to protect the confidentiality, reliability, and availability of digital images on online processing applications, it is crucial to increase the infosecurity of these images. Therefore, an authorization encryption scheme should ensure a high security level of digital images. The present study aimed to establish a multilayer convolutional processing network (MCPN)-based cryptography mechanism for performing two-round image encryption and decryption processes. In the MCPN layer, two-dimensional (2D) spatial convolutional operations were used to extract the image features and perform scramble operations from grayscale to gray gradient values for the first-image encryption and second-image decryption processes, respectively. In the MCPN weighted network, a sine-power chaotic map (SPCM)-based key generator was used to dynamically produce the non-ordered pseudorandom numbers to set the network-weighted values as secret keys in a sufficiently large key space. It performs the second and first encryption processes using the diffusion method, modifying the image pixel values. Children's headshots and medical images were used to evaluate the security level by comparing the plain and cipher images using the information entropy, number of pixel change rate, and unified averaged changed intensity indices. Moreover, the plain and decrypted images were compared to verify the decrypted image quality using the structural similarity index measurement and peak signal-to-noise ratio. [ABSTRACT FROM AUTHOR]

Different ethnic communities traditionally use herbal medicines to treat different curable and incurable diseases. The main purpose of this research was to assess the antibacterial and cytotoxic potential of different polarities extracts of unripe bananas collected from Omani farmers. The antibacterial and cytotoxic potential of the prepared extracts were assessed against the gram + and - antibacterial strains and brine shrimp lethality (BSL) bioassays. All prepared extracts at dissimilar concentrations exhibited acceptable antibacterial potential against two Gram-positive and two Gramnegative bacteria strains with a diameter of inhibition range of 0- 11.5 mm. The maximum antibacterial activity among the plant extracts was obtained from hexane extract against E. coli. The cytotoxic results exposed that all polarities unripe banana extracts at each concentrations lethaled the shrimp larvae at all applied concentrations. Among the six polarities extracts of unripe banana from Sohar and Dhofar, the butanol and hexane extracts exhibited significant cytotoxic potential with an LC50 value of 20.12±0.10; 26.19±0.57 and 22.39±0.11; 27.88±0.17 µg/ml. The lesser potential found in ethyl acetate extract among the six extracts with an LC50 value of 36.68±0.22 and 49.32±0.16 µg/ml. The results displayed that non-polar unripe banana extract has substantial antibacterial and cytotoxic potential. Therefore, the significant extract from the unripe banana can be used further for isolation of biologically active ingredients against a number of ailments. [ABSTRACT FROM AUTHOR]

The aim of this study was to focus on the evaluation of the antimicrobial activity of honey samples and ethanolic extract of propolis (EEP) against Candida species. The honey concentrations - 50 % and 25 % of honey in distilled water were prepared. These preparations were tested for antimicrobial activity against five different types of yeasts: Candida crusei, Candida albicans, Candida (Torulopsis) glabrata, Candida parapsilosis and Candida tropicalis. The disc diffusion method using filter paper discs was employed. The antimicrobial activity was determined as an equivalent of the inhibition zones diameters (in millimeters) after incubation of the cultures for 48 hours. There were not seen an inhibition zones against the yeasts investigated in the 25 % and 50 % concentration of honey samples. The analysis among the tested yeasts showed that Candida crusei was the most sensitive in 70 % of EEP, and the sensitivity of the yeasts decreased in the order: Candida albicans > Candida parapsilosis > Candida tropicalis > Candida glabrata.

Using the heavy rare earth Dy element to improve coercivity is the most common solution for hindering the reduction in magnetic properties in the Nd–Fe–B magnet, and the effective utilization of Dy has become the focus of research in industrial society. In this work, we investigated the influence of DyHx addition and diffusion methods on the microstructure, magnetic performance, and thermal stability of the Nd–Y–Fe–B magnet with a Y-rich core structure. The coercivity of the DyHx addition magnet increases from 9.45 kOe to 15.51 kOe when adding 1.6 wt.% DyHx, while the DyHx diffusion magnet increases to 15.15 kOe. According to the analysis of the microstructure and elemental distribution, both Dy-rich shells were basically formed due to the diffusion process of Dy atoms. The Dy-rich shell in the DyHx addition magnet was similar with the original core–shell structure in the Nd–Y–Fe–B magnet. However, the distinct dual-shell structure consisting of a thinner Dy-rich shell and a Y-lean shell was constructed in the DyHx diffused magnet, contributing to the superior coercivity increment and Dy utilization efficiency. Furthermore, the remanence of the DyHx diffused magnet is up to 12.90 kG, which is better than that of the DyHx addition magnet (12.59 kG), due to fewer Dy atoms entering the 2:14:1 matrix grain to cause the antiferromagnetic coupling with Fe atoms. Additionally, the thermal stability of the DyHx diffusion magnet is also better than that of the DyHx addition magnet, owing to the elevated coercivity at room temperature, which expands the application range of the Nd–Y–Fe–B magnet to a certain extent. [ABSTRACT FROM AUTHOR]

Copyright of Farmacia is the property of Societatea de Stiinte Farmaceutice Romania and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Using the heavy rare earth Dy element to improve coercivity is the most common solution for hindering the reduction in magnetic properties in the Nd–Fe–B magnet, and the effective utilization of Dy has become the focus of research in industrial society. In this work, we investigated the influence of DyHx addition and diffusion methods on the microstructure, magnetic performance, and thermal stability of the Nd–Y–Fe–B magnet with a Y-rich core structure. The coercivity of the DyHx addition magnet increases from 9.45 kOe to 15.51 kOe when adding 1.6 wt.% DyHx, while the DyHx diffusion magnet increases to 15.15 kOe. According to the analysis of the microstructure and elemental distribution, both Dy-rich shells were basically formed due to the diffusion process of Dy atoms. The Dy-rich shell in the DyHx addition magnet was similar with the original core–shell structure in the Nd–Y–Fe–B magnet. However, the distinct dual-shell structure consisting of a thinner Dy-rich shell and a Y-lean shell was constructed in the DyHx diffused magnet, contributing to the superior coercivity increment and Dy utilization efficiency. Furthermore, the remanence of the DyHx diffused magnet is up to 12.90 kG, which is better than that of the DyHx addition magnet (12.59 kG), due to fewer Dy atoms entering the 2:14:1 matrix grain to cause the antiferromagnetic coupling with Fe atoms. Additionally, the thermal stability of the DyHx diffusion magnet is also better than that of the DyHx addition magnet, owing to the elevated coercivity at room temperature, which expands the application range of the Nd–Y–Fe–B magnet to a certain extent.

Three new metal complexes of 4‐(benzylideneamino)‐5‐phenyl‐4H‐1,2,4‐triazole‐3‐thiol ligand (L) and three transition metal ions: Fe (III), Cu (II), and Zn (II) were synthesized and characterized. The ligand derived from 4‐amino‐5‐phenyl‐1,2,4‐triazole‐3‐thiol and benzaldehyde was synthesized in a 1:1 molar ratio. All the chelates were characterized by elemental analysis, conductivity measurements, thermal analysis, FT‐IR, and 1H‐NMR spectroscopy. The IR spectrum revealed that the Schiff base ligand coordinated in a neutral bidentate manner with the metal ions through the azomethine N and thiol S. The thiol group coordinated to the metal ions without proton displacement as confirmed from the 1H NMR spectra. The conductivity data showed the electrolytic nature of the Fe (III) and Cu (II) complexes while the Zn (II) complex was nonelectrolyte. All metal complexes had octahedral structure as depicted by spectral and elemental analyses. The complexes start decomposition at 35°C, and they decomposed in four to five steps. The scanning electron microscope (SEM) analysis confirmed the presence of metal complexes in nanostructure. The 1,2,4‐triazole Schiff base ligand (L) and its transition metal complexes have been screened for their antibacterial (Gram [+] bacteria): Bacillis subtilis and Staphylococcus aureus, (Gram [−] bacteria): Escherichia coli and Pseudomonas aeruginosa and two fungi: Candida albicans and Aspergillus flavus by agar diffusion method. The two metal complexes were subjected to molecular docking study against crystal structure of Aspergillus fumigatus (PDB ID: 6NE0) and crystal structure of Mycobacterium tuberculosis (PDB ID: 5UHF). The mode of binding between the A. fumigatus (PDB ID: 6NE0) and Mycobacterium tuberculosis strains and the complexes was discussed. [ABSTRACT FROM AUTHOR]

The paper presents data on the level of biotoxicity and biosorption of heavy metals using the example of iron in relation to various strains of Bacillus subtilis. Our experimental data show a high level of biotoxicity of iron compounds for all B. subtilis strains that were tested,with iron nitrate having the highest inhibitory action at minimal concentrations (0.063 moles/l) and iron chloride being the least toxic among the studied salts. Atomic force microscopy revealed the absence of active interaction between iron cations and vegetative forms of bacterial cells with no lysing effect on the latter. As concentrations in the borderline growth zone decrease, the densities of spore-forming forms of the microorganisms increase and metal complexes on their surfaces decrease to nil, which indicates the negative effect of certain concentrations of iron cations in relation to vegetative forms of the test organisms. The proposed technique allows assessment of the degree of interaction of metal cations and bacterial cells when cultivating on the surface of the medium excluding the option of accidental sedimentation of cells and the absence of metal complexes that can form in the structure of the liquid substrate and precipitate on the cell population while being centrifuged. [ABSTRACT FROM AUTHOR]

Standard gases are often prepared using high-pressure gas cylinders. However, it is difficult to accurately prepare a known concentration of hydrogen chloride (HCl) gas using this method because HCl is highly corrosive and adsorptive. In this study, a simple method for the continuous generation of HCl gas was developed using a diffusion tube containing hydrochloric acid and a nitrogen carrier gas. The concentration of HCl produced from this system was almost unstable, but constant gas generation was realized for several hours when azeotropic hydrochloric acid (20.6% HCl in water) and a temperature near the azeotropic point (108.5 °C) were used, resulting in the generation of 103.6 ppm (mean, n = 5) of HCl gas with a relative standard deviation (RSD) of 2.34%. In this case, the percentage of HCl present in the entire gas mixture of HCl and water vapor was 22.5%, which is almost equivalent to the HCl content in the azeotropic hydrochloric acid (20.6%). The HCl concentration could also be controlled by changing the flow rate of the carrier gas. This work demonstrates a simple technique based on the diffusion theory that allows for the constant, controllable generation of a known concentration of HCl gas using an azeotropic hydrochloric acid system.

The authors report a novel, effective and enhanced method of conjugating anticancer drug, paclitaxel and gallic acid with magnetosomes. Here, anticancer drugs were functionalised with magnetosomes membrane by direct and indirect (via crosslinkers: glutaraldehyde and 3‐aminopropyltriethoxysilane) adsorption methods. The prepared magnetosome–drug conjugates were characterised by Fourier transform infrared, zeta potential, field‐emission scanning electron microscope and thermogravimetric analysis/differential scanning calorimetry. The drug‐loading efficiency and capacity were found to be 87.874% for paclitaxel (MP) and 71.3% for gallic acid (MG), respectively as calculated by ultraviolet spectroscopy and high‐performance liquid chromatography. The drug release demonstrated by the diffusion method in phosphate buffer (PBS), showing a prolonged drug release for MP and MG, respectively. The cytotoxicity effect of the MP and MG displayed cytotoxicity of 69.71%, 55.194% against HeLa and MCF‐7 cell lines, respectively. The reactive oxygen species, acridine orange and ethidium bromide and 4, 6‐diamidino‐2‐phenylindole staining of the drug conjugates revealed the apoptotic effect of MP and MG. Further, the regulation of tumour suppressor protein, p53 was determined by western blotting which showed an upregulation of p53. Comparatively, the magnetosome–drug conjugates prepared by direct adsorption achieved the best effects on the drug‐loading efficiency and the increased percentage of cancer cell mortality and the upregulation of P53. The proposed research ascertains that magnetosomes could be used as effective nanocarriers in cancer therapy. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus is one of the most resistant Gram-positive bacteria, capable of producing serious infections difficult to treat. The purpose of this paper is to show the inhibitory property of some essential oils against this species. The antibacterial action of herbal essential oils has been extensively studied but their effectiveness differs depending on the origin of the essential oil, the extraction method, and the plant parts from which the extraction was made. The essential oils used in this study are widely marketed oils from different producers. Overall, 19 essential oils were tested: oregano, garden thyme, wild thyme, lavender, peppermint, basil, rosemary, fennel, cumin, black cumin, dill, garden sage, grapefruit, bay laurel, patchouli, and tea tree. The bacteria tested for sensitivity to these essential oils was Staphylococcus aureus, obtained from the "Horia Cernescu" Research Laboratory Complex of the "King Michael I of Romania" University of Agricultural Sciences and Veterinary Medicine of Banat in Timisoara, Romania. The method used was the Kirby-Bauer diffusion method, commonly used to test the antibiotic sensitivity of various bacteria. The culture medium used to grow bacteria was supplemented with blood. For the interpretation of the results, a classification of essential oils was carried out according to the inhibition zone diameter (IZD). For oils with an IZD larger than 20 mm, Staphylococcus aureus has been characterized as highly sensitive; for a diameter between 15 and 19 mm, it has been characterized as very sensitive; in the case of diameters of 9-14 mm, it has been called sensitive; it was considered non-sensitive for diameters smaller than 8 mm. Thus, oregano, garden thyme, wild thyme, clove, and vervain oils have been classified in the extremely sensitive category. Bay laurel, patchouli, peppermint, and tea tree oils have been classified as highly sensitive, and lavender, basil, dill, rosemary, garden sage, rose geranium, and cumin oils have been classified as sensitive. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Image & Graphics is the property of Editorial Office of Journal of Image & Graphics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to establish more accurately and rapid pretreatment method for the nitrogen stable isotope analysis of soil ammonium nitrogen, diffusion and N2O produced method were compared, and combined with two commercially available equipment’s, i.e., elemental analyzer-isotope ratio mass spectrometer（Flash HT-IRMS） and trace gas preconcentration-stable isotope mass spectrometry（PreCon-IRMS）, respectively, for the analysis of the nitrogen stable isotope abundance inammonium sulfate reference solutions and soil ammonium nitrogen extracted from different paddy soil samples. The stable isotope measurement results showed that both the diffusion and N2O produced method coupled IRMS analytical systems were able to provide good analytical data for ammonium sulfate reference solutions in accuracy with precision of superior to 0.5% and 0.2%, respectively. However, there was a nitrogen isotope fractionation accrued in the diffusion-treated process, and the test results needed to be corrected by a standard curve. At the same time, the 15N-stable isotope abundance in ammonium nitrogen extracted from different paddy soils were determined by diffusion and N2O produced method. The comparison of the analytical data from the two analytical methods indicated that N2O produced method coupled with PreCon-IRMS provided better nitrogen stable isotope data in reproducibility and accuracy than the data obtained by the other method. In addition, through the auxiliary automatic trace nitrogen conversion-N2O generated device, nitrogen stable isotope abundance of soil ammonium nitrogen could be simultaneously analysis online in batch process, and the pretreatment analysis time was short, the sample consumption was small, only need 10 μg N for one sample（<5 mL soil extract solution）. Therefore, for the analysis of nitrogen isotopes in micro-amounts of soil ammonium, the N2O produced method coupled with PreCon-IRMS analysis method has more advantages than the diffusion method coupled Flash HT-IRMS analysis method. [ABSTRACT FROM AUTHOR]

The key to improve the application of MgB2 is to improve its critical current density Jc at high magnetic fields. The graphene and reduced graphene oxide (rGO) are added to MgB2 bulks to contribute to the flux pinning and Jc improvement. Graphene and rGO are added in the ratio of C:B = x:1−x, in which x = 0–5 wt% to the MgB2 bulks. The effects of the graphene and rGO addition on the superconducting properties of MgB2 bulks are investigated. The dense and uniform MgB2 bulks are obtained by diffusion method with the addition of graphene and rGO. The superconducting transition temperature Tc decreases with increasing graphene and rGO addition. The Tc of the rGO-added sample declines more dramatic than that of the graphene-added sample. The addition of graphene and rGO (in the ratio C:B = x:1−x, where x = 1–5 wt%) to the MgB2 shows the improved Jc at whole range of magnetic fields compared with the no-added MgB2 sample, except for the MgB2 sample with 5 wt% of rGO addition. The sample with 1 wt% rGO addition exhibits the highest Jc value, which is attributed to the improvement of intergrain connectivity and flux pinning caused by appropriate amount of rGO addition. However, nonsuperconducting phase MgB2C2 appears and MgO content increases in the MgB2 bulk samples with 5 wt% rGO addition, which result in the reduction in Jc. [ABSTRACT FROM AUTHOR]

MgB 2 bulks with a density of 1.95 g/cm 3 , were prepared by an improved Mg-diffusion method. The effects of different heat treatments on superconducting transitions temperature T c and critical current density J c of MgB 2 were investigated. The MgB 2 synthesized by the optimal heat treatment has the T c of 38.1 K and J c of 0.53 MA/cm 2 at 10 K, self-field. In order to improve poor high field properties in a diffusion method, nano-Pr 6 O 11 and C doping effects on J c and the irreversible field, H irr of MgB 2 were also studied. The results show that at 10 K and 6 T the J c for 15 at% C-doped MgB 2 reaches 10 4 A/cm 2 , which is almost two orders of magnitude higher than that of the undoped one, and better than that of the nano-C doped MgB 2 prepared by solid-state reaction. For the nano-Pr 6 O 11 -doped MgB 2 , the J c also increases by a factor of 9.4 than that of the pure sample at 10 K and 2 T. According to a lot of experimental results and theoretic analyses, we propose that the combination of the improved Mg-diffusion method and chemical doping of nanoparticles or C, may be an efficient approach to make the MgB 2 have excellent J c and H irr capability in whole magnetic field. [ABSTRACT FROM AUTHOR]

A study of the effects of graphene doping on the superconducting properties of MgB2 bulks prepared by the diffusion method has been conducted over a range of doping levels of 0–30 wt%. The increase in a large quantity of a C-containing nonsuperconducting phase together with the effects of C-substitution on the phase itself results in a change of superconducting properties. While the transition temperature Tc monotonically decreases with increasing graphene addition, the critical current density Jc is increased for small graphene additions due to the larger volume fraction of the superconducting phase. Larger additions resulted in larger quantities of the nonsuperconducting phase and consequently these samples have a lower Jc. [ABSTRACT FROM PUBLISHER]

The current time increase in the prevalence of antibiotic resistant 'super‐bugs' and the risks associated with food safety have become global issues. Therefore, further research is warranted to identify new and effective antimicrobial substances. Silver nanoparticles (Ag‐NPs) were synthesized by autoclaving technique using, different concentrations of Ag salt (AgNO3) solution (1, 5, 10, and 25 mM). Their presence was confirmed by a surface plasmon resonance band at ∼435 nm using UV–Vis absorption spectra. The morphology of the synthesized Ag‐NPs stabilized by polyacrylamide (PAM) was examined by TEM, SAED, and EDS. TEM images revealed that the synthesized Ag‐NPs had an average diameter of 2.98±0.08 nm and SAED and EDS results confirmed the formation of Ag‐NPs. In addition, FT‐IR spectroscopy revealed that a PAM polymer matrix stabilized the Ag‐NPs. The well diffusion method, was used to test, Gram positive and Gram negative bacteria were examined. Also the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were studied against Ag‐NPs. The Ag‐NPs exhibited strong inhibitory activity, MIC and MBC against the tested clinical bacterial isolates. These results suggest that Ag‐NPs stabilized in PAM are highly effective against clinical bacterial isolates can be applied in medical fields. [ABSTRACT FROM AUTHOR]

When the δ15N-NH4+ in water samples is pretreated by using the ion exchange and diffusion method with NH4Cl and KCl, the key problem is how to reduce the blank, avoid isotopic fractionation and yield accurate isotope results. In this study, a closed ion exchange system was set up to prevent the small amount of NH4+ contamination to the water samples. Furthermore, the sample and elution flow rates of 1.2 L/h and 0.2 L/h respectively were achieved by adjusting the speed of a peristaltic pump. Thus, both the experiment time and the contamination were reduced. In addition, all of the NH4+ in the sample is absorbed on the ion exchange resin and the N recoveries were from 93.5% to 102.8%. Therefore, the whole process will not cause isotopic fractionation. The blank introduced by KCl was reduced by being heated at 450℃ for 24 h. As a result, the blank ion exchange was reduced to below the detection limit of 0.02 mg/L by using the closed ion exchange system. The problem of contamination for water sample pretreatment in air was solved. The process was accelerated and efficiency was improved

Purpose: To investigate the efficiency of silver nanoparticles synthesized by wet chemical method, and evaluate their antibacterial and anti-cancer activities. Methods: Wet chemical method was used to synthesize silver nanoparticles (AgNPs) from silver nitrate, trisodium citrate dehydrate (C6H5O7Na3.2H2O) and sodium borohydride (NaBH4) as reducing agent. The AgNPs and the reaction process were characterized by UV-visible spectrometry, zetasizer, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). The antibacterial and cytotoxic effects of the synthesized nanoparticles were investigated by agar diffusion method and MTT assay respectively. Results: The silver nanoparticles formed were spherical in shape with mean size of 10.3 nm. The results showed good antibacterial properties, killing both Gram-positive and Gram-negative bacteria, and its aqueous suspension displayed cytotoxic activity against colon adenocarcinoma (HCT-116) cell line. Conclusion: The findings indicate that silver nanoparticles synthesized by wet chemical method demonstrate good cytotoxic activity in colon adenocarcinoma (HCT-116) cell lines and strong antibacterial activity against various strains of bacteria. [ABSTRACT FROM AUTHOR]

Antibiotic residue can have a harmful effect on human health and can disrupt the processing of milk and milk products. In order to prevent these unwanted effects of residue, different screening methods are used today. The basic goal of this paper is to compare screening methods performed during the testing of milk from different points of the production chain. In this paper we have comparatively analyzed three screening methods: microbiological methods - the Delvo SP test and the diffusion method with B. stearothermophilus as the test microorganism, and an enzyme method - the Penzym S test. Twenty samples of farm milk from collective tanks were analyzed, as well as 20 samples of milk from transport cisterns, 10 samples of pasteurized milk and 10 samples of sterilized market milk. Based on the comparative analysis of the diffusion method, Delvo SP test and Panzym S test, we conclude that all three methods are in hgih mutual accordance (the kappa value oscillates from nearly ideal to ideal coinciding) and thus meet one of the criteria for being included in the systematic control of milk for the presence of antibiotic residue.

Standard gases are often prepared using high-pressure gas cylinders. However, it is difficult to accurately prepare a known concentration of hydrogen chloride (HCl) gas using this method because HCl is highly corrosive and adsorptive. In this study, a simple method for the continuous generation of HCl gas was developed using a diffusion tube containing hydrochloric acid and a nitrogen carrier gas. The concentration of HCl produced from this system was almost unstable, but constant gas generation was realized for several hours when azeotropic hydrochloric acid (20.6% HCl in water) and a temperature near the azeotropic point (108.5 °C) were used, resulting in the generation of 103.6 ppm (mean, n = 5) of HCl gas with a relative standard deviation (RSD) of 2.34%. In this case, the percentage of HCl present in the entire gas mixture of HCl and water vapor was 22.5%, which is almost equivalent to the HCl content in the azeotropic hydrochloric acid (20.6%). The HCl concentration could also be controlled by changing the flow rate of the carrier gas. This work demonstrates a simple technique based on the diffusion theory that allows for the constant, controllable generation of a known concentration of HCl gas using an azeotropic hydrochloric acid system. [ABSTRACT FROM AUTHOR]

Abstract: Zeolitic Imidazolate framework (ZIF-90) polyhedron (Zn(ICA)-1) was synthesized via diffusion of triethlyamine (TEA) and hexane solution into the N,N′-dimethylformamide (DMF) solution of imidazole-2-carboxyaldehyde (ICA) and Zn(NO3)2·6H2O at room temperature. And suprastructure (Zn(ICA)-2) were synthesized via direct addition of TEA to the N,N′-dimethylformamide (DMF) solution of imidazole-2-carboxyaldehyde (ICA) and Zn(NO3)2·6H2O at room temperature. The scanning electron microscopy (SEM) measurement indicated that the sample of Zn(ICA)-1 showed polyhedron morphology with the diameter of 300–400nm and the sample of Zn(ICA)-2 showed super-structural morphology. XRD results indicated that Zn(ICA)-1 has the crystalline structure of ZIF-90 and Zn(ICA)-2 is amorphous. The gases adsorption measurement results showed that the sample Zn(ICA)-2 exhibited mesoporous structure. [Copyright &y& Elsevier]

We propose an adaptive diffusion mechanism to optimize global cost functions in a distributed manner over a network of nodes. The cost function is assumed to consist of a collection of individual components. Diffusion adaptation allows the nodes to cooperate and diffuse information in real-time; it also helps alleviate the effects of stochastic gradient noise and measurement noise through a continuous learning process. We analyze the mean-square-error performance of the algorithm in some detail, including its transient and steady-state behavior. We also apply the diffusion algorithm to two problems: distributed estimation with sparse parameters and distributed localization. Compared to well-studied incremental methods, diffusion methods do not require the use of a cyclic path over the nodes and are robust to node and link failure. Diffusion methods also endow networks with adaptation abilities that enable the individual nodes to continue learning even when the cost function changes with time. Examples involving such dynamic cost functions with moving targets are common in the context of biological networks. [ABSTRACT FROM PUBLISHER]

The surface engineering of titanium with TiCxO1−x coatings through diffusion carbo-oxidising from graphite in oxygen containing media is investigated. The effect of oxygen partial pressure on phase composition of coatings during carbo-oxidising is evaluated. The interval of oxygen partial pressure allowing the carbo-oxide TiCxO1−x to form is defined as 10−2-103 Pa. The effects of process temperature and time on evolution of TiCxO1−x composition and morphology of surface layer have been investigated. It is determined that increases in temperature and process time favour an increase in carbon content in TiCxO1−x. It is revealed that at temperatures above the transformation temperature Tα⇔ β, TiCxO1−x is formed not only in coating but also throughout grain boundaries of diffusion layer. The stages of carbo-oxide formation during diffusion carbo-oxidising of commercially pure titanium are explained as follows: surface saturation with oxygen; formation of TiO2 film; oxide dissolution and formation of diffusion layer; formation of non-stoichiometric TiCx and TiOx and their interaction resulting in TiCxO1−x formation. Corrosion properties of carbo-oxide coatings tested in 80%H2SO4 are compared with nitride and oxide coatings. It is revealed that carbo-oxide coating demonstrates better corrosion resistance. The tribological properties of carbo-oxide, nitride and oxide coatings tested with bronze counterbody are compared, and carbo-oxide coating demonstrates better wear resistance. [ABSTRACT FROM AUTHOR]

Abstract: Copper(II), cobalt(II) and nickel(II) complexes of hydrazone ligand (SAPH) derived from salicylaldehyde and phenylhydrazine have been encapsulated in zeolite-Y super cages via ship-in-a-bottle synthesis. Detailed characterization of the intrazeolitic complexes were performed by elemental analysis, spectral (FT-IR, UV–Vis.) studies, magnetic measurements and X-ray diffraction. Furthers, surface texture and thermal analysis (TG, DTG, DTA) have provided further evidence for successful immobilization of the metal complexes inside zeolite Y. Investigation of the stereochemistry of these incorporated chelates pointed out that, SAPH ligand is capable to coordinate with the central metal through the (Clic (OH) and (NH) groups forming polynuclear structures. The involvement of zeolite oxygen in coordination was postulated in the hybrid materials. The intrazeolitic copper, cobalt and nickel–SAPH complexes have distorted tetrahedral, octahedral and square-pyramidal configurations, respectively. The zeolite encapsulated complexes are thermally stable up to 800°C except Cu(II) sample which is thermally stable up to midpoint 428°C. The assessment of the catalytic activity was performed by the use of the photo-degradation of acid violet-1 dye as a probe reaction in presence of H2O2 as an oxidant. Decolorization of acid violet-1 dye was examined under the same conditions whereas the unpromoted zeolite and CuII, CoII, NiII–hydrazone complexes supported on zeolite showed 13% and 76%, 53%, 43% color removal, respectively. The results revealed that, the zeolite encapsulated Cu(II) complex generally exhibited better catalytic efficiency (76%) compared with other investigated zeolite encapsulated metal–hydrazone samples. [Copyright &y& Elsevier]