Synthesis and Magnetic Properties of Hematite Particles in a “Nanomedusa” Morphology

Lee, Jin Bae,Kim, Hae Jin,Lu&#x17e,nik, Janez,Jelen, Andreja,Paji&#x107,, Damir,Wencka, Magdalena,Jagli&#x10d,i&#x107,, Zvonko,Meden, Anton,Dolin&#x161,ek, Janez Hindawi Limited 2014 Journal of nanomaterials Vol.2014 No.-

<P>We present the synthesis, characterization, and magnetic properties of hematite particles in a peculiar “nanomedusa” morphology. The particles were prepared from an iron-silica complex by a hydrothermal process in a solution consisting of ethyl acetate and ethanol. The particles’ morphology, structure, and chemical composition were investigated by transmission electron microscopy, powder X-ray diffraction, and scanning electron microscope equipped with an energy-dispersive X-ray spectrometer. The “hairy” particles consist of a spherical-like core of about 100 nm diameter and fibrous exterior composed of thin “legs” of 5 nm diameter grown along one preferential direction. The particles’ cores are crystalline and undergo a magnetic phase transition to a weakly ferromagnetic state at a temperature of 930 K that matches reasonably the Néel temperature of bulk hematite. However, unlike bulk hematite that undergoes Morin transition to an antiferromagnetic state around room temperature and small hematite nanoparticles that are superparamagnetic, the “nanomedusa” particles remain weakly ferromagnetic down to the lowest investigated temperature of 2 K. Each particle thus represents a nanodimensional “hairy” ferromagnet in a very broad temperature interval, extending much above the room temperature. Such high-temperature ferromagnetic nanoparticles are not frequently found among the nanomaterials.</P>

Effects of Keratinase on Performance, Nutrient Utilization, Intestinal Morphology, Intestinal Ecology and Inflammatory Response of Weaned Piglets Fed Diets with Different Levels of Crude Protein

Wang, D.,Piao, X.S.,Zeng, Z.K.,Lu, T.,Zhang, Q.,Li, P.F.,Xue, L.F.,Kim, S.W. Asian Australasian Association of Animal Productio 2011 Animal Bioscience Vol.24 No.12

Two experiments were conducted to investigate the in vitro ability of keratinase to hydrolyze soybean glycinin and ${\beta}$-conglycinin and to evaluate the in vivo effects of keratinase when included in corn-soybean diets with different levels of crude protein and fed to nursery pigs. In experiment 1, a saturated keratinase solution (1 ml) was added to two blank controls of either glycinin or ${\beta}$-conglycinin resulting in the hydrolysis of 94.74% glycinin and 88.89% ${\beta}$-conglycinin. In experiment 2, 190 pigs (8.3${\pm}$0.63 kg BW) were allotted to one of four treatments in a 2${\times}$2 factorial arrangement on the basis of body weight, and sex was balanced among the pens. The effects of crude protein (19 vs. 22%) and keratinase (0 vs. 0.05%) were studied. Each treatment was applied to six pens with seven (two pens) or eight pigs per pen. Pigs were fed the experimental diets for 21 d. Weight gain and feed conversion ratio were improved (p<0.05) with keratinase supplementation while feed intake was reduced (p<0.05). Keratinase supplementation increased (p<0.05) the apparent total tract digestibility of dry matter, energy, crude protein and phosphorus. Keratinase supplementation also increased n-butyric acid in the cecum and colon, lactobacilli and total anaerobe counts in the colon as well as the ratio of villus height to crypt depth in the ileum. Additionally, fecal score, ammonia nitrogen and branch chain volatile fatty acids in the colon, E. coli and total aerobe counts in the colon, crypt depth in the jejunum and ileum as well as serum interleukin-1 and interleukin-6 concentrations were also decreased (p<0.05) by keratinase supplementation. A reduction in dietary crude protein decreased (p<0.05) colon ammonia nitrogen concentration and cecal propionic acid and branch chain volatile fatty acid concentrations. In addition, cecal E. coli counts, colon total anaerobe counts, ileal crypt depth, and serum interleukin-1 and interleukin-6 concentrations were also decreased (p<0.05) with the reduction of dietary crude protein. With the exception of fecal scores, there were no significant interactions between crude protein and keratinase. This study provides evidence that dietary keratinase supplementation improved nursery pig performance by improving intestinal morphology and ecology, thus improving nutrient digestibility and alleviating the inflammatory response.

Feasibility of Atmospheric-Pressure CO Cold Plasma for Reduction of Supported Metal Ions

Di, L.,Zhang, X.,Lee, B.,Lu, P.,Ahn, W. S.,Park, D. W. Springer Science + Business Media 2017 Plasma chemistry and plasma processing Vol.37 No.6

<P>An atmospheric pressure (AP) carbon monoxide (CO) cold plasma method was developed and employed to reduce supported metal ions for the first time. HAuCl4, AgNO3, H2PtCl6, and Pd(NO3)(2) ions supported on a commercial sample of TiO2 (Degussa P25) were reduced by AP CO cold plasma. The results of UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS) and X-ray photoelectron spectroscopy (XPS) indicate that the supported metal ions are reduced to their metallic states. Au/P25-CP and Au/P25-HP were prepared by CO and H-2 cold plasma, respectively, to investigate the reduction ability of CO cold plasma. XPS and transmission electron spectroscopy analyses show that the gold nanoparticles in Au/P25-CP and Au/P25-HP exist in the form of metallic gold, and exhibit similar size. Interestingly, a blue shift of the surface plasmon resonance peak was observed for Au/P25-CP because of the amorphous carbon formed by CO dissociation. In situ optical emission spectrum of the CO cold plasma was recorded and excited CO molecules were deemed to be the reducing agents. CO cold plasma was also adopted to reduce P25 supported copper ions, while metallic copper nanoparticles were obtained accompanied by a certain amount of oxidized copper species. AP CO cold plasma is as effective as H-2 plasma for reducing supported metal ions, and has great potential for tuning the SPR absorption.</P>

Organic Zener Diodes: Tunneling across the Gap in Organic Semiconductor Materials

Kleemann, Hans,Gutierrez, Rafael,Lindner, Frank,Avdoshenko, Stanislav,Manrique, Pedro D.,Lu&#x308,ssem, Bjo&#x308,rn,Cuniberti, Gianaurelio,Leo, Karl American Chemical Society 2010 Nano letters Vol.10 No.12

<P>Organic Zener diodes with a precisely adjustable reverse breakdown from −3 to −15 V without any influence on the forward current−voltage curve are realized. This is accomplished by controlling the width of the charge depletion zone in a pin-diode with an accuracy of one nanometer independently of the doping concentration and the thickness of the intrinsic layer. The breakdown effect with its exponential current voltage behavior and a weak temperature dependence is explained by a tunneling mechanism across the highest occupied molecular orbital−lowest unoccupied molecular orbital gap of neighboring molecules. The experimental data are confirmed by a minimal Hamiltonian model approach, including coherent tunneling and incoherent hopping processes as possible charge transport pathways through the effective device region.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2010/nalefd.2010.10.issue-12/nl102916n/production/images/medium/nl-2010-02916n_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nl102916n'>ACS Electronic Supporting Info</A></P>

Record-setting algal bloom in Lake Erie caused by agricultural and meteorological trends consistent with expected future conditions

Michalak, Anna M.,Anderson, Eric J.,Beletsky, Dmitry,Boland, Steven,Bosch, Nathan S.,Bridgeman, Thomas B.,Chaffin, Justin D.,Cho, Kyunghwa,Confesor, Rem,Dalo&#x11f,lu, Irem,DePinto, Joseph V.,Evans, M National Academy of Sciences 2013 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.110 No.16

<P>In 2011, Lake Erie experienced the largest harmful algal bloom in its recorded history, with a peak intensity over three times greater than any previously observed bloom. Here we show that long-term trends in agricultural practices are consistent with increasing phosphorus loading to the western basin of the lake, and that these trends, coupled with meteorological conditions in spring 2011, produced record-breaking nutrient loads. An extended period of weak lake circulation then led to abnormally long residence times that incubated the bloom, and warm and quiescent conditions after bloom onset allowed algae to remain near the top of the water column and prevented flushing of nutrients from the system. We further find that all of these factors are consistent with expected future conditions. If a scientifically guided management plan to mitigate these impacts is not implemented, we can therefore expect this bloom to be a harbinger of future blooms in Lake Erie.</P>

COMBUSTION VISUALIZATION AND EMISSIONS OF A DIRECT INJECTION COMPRESSION IGNITION ENGINE FUELED WITH BIO-DIESOHOL

X. LU,Z. HUANG,W. ZHANG,D. LI 한국자동차공학회 2005 International journal of automotive technology Vol.6 No.1

The purpose of this paper is to experimentally investigate the engine pollutant emissions and combustion characteristics of diesel engine fueled with ethanol-diesel blended fuel (bio-diesohol). The experiments were performed on a single-cylinder DI diesel engine. Two blend fuels were consisted of 15% ethanol, 83.5% diesel and 15% solublizer (by volume) were evaluated one without cetane improver (E15-D) and one with a cetane improver (E15-D+CN improver). The engine performance parameters and emissions including fuel consumption, exhaust temperature, lubricating oil temperature, Bosch smoke number, CO, NOx, and THC were measured, and compared to the baseline diesel fuel. In order to gain insight into the combustion characteristics of bio-diesohol blends, the engine combustion processes for blended fuels and diesel fuel were observed using an Engine Video System (AVL 513). The results showed that the brake specific fuel consumption (BSFC) increased at overall engine operating conditions, but it is worth noting that the brake thermal efficiency (BTE) increased by up to 1-23% with two blends when compared to diesel fuel. It is found that the engine fueled with ethanol-diesel blend fuels has higher emissions of THC, lower emissions of CO, NOx, and smoke. And the results also indicated that the cetane improver has positive effects on CO and NOx emissions, but negative effect on THC emission. Based on engine combustion visualization, it is found that ignition delay increased, combustion duration and the luminosity of flame decreased for the diesohol blends. The combustion is improved when the CN improver was added to the blend fuel.

Effect of bamboo and rice straw biochars on the mobility and redistribution of heavy metals (Cd, Cu, Pb and Zn) in contaminated soil

Lu, K.,Yang, X.,Gielen, G.,Bolan, N.,Ok, Y.S.,Niazi, N.K.,Xu, S.,Yuan, G.,Chen, X.,Zhang, X.,Liu, D.,Song, Z.,Liu, X.,Wang, H. Academic Press 2017 Journal of Environmental Management Vol.186 No.2

<P>Biochar has emerged as an efficient tool to affect bioavailability of heavy metals in contaminated soils. Although partially understood, a carefully designed incubation experiment was performed to examine the effect of biochar on mobility and redistribution of Cd, Cu, Pb and Zn in a sandy loam soil collected from the surroundings of a copper smelter. Bamboo and rice straw biochars with different mesh sizes (<0.25 mm and <1 mm), were applied at three rates (0, 1, and 5% w/w). Heavy metal concentrations in pore water were determined after extraction with 0.01 M CaCl2. Phytoavailable metals were extracted using DTPA/TEA (pH 7.3). The European Union Bureau of Reference (EUBCR) sequential extraction procedure was adopted to determine metal partitioning and redistribution of heavy metals. Results showed that CaCl2-and DTPA-extractable Cd, Cu, Pb and Zn concentrations were significantly (p < 0.05) lower in the bamboo and rice straw biochar treated soils, especially at 5% application rate, than those in the unamended soil. Soil pH values were significantly correlated with CaCl2-extractable metal concentrations (p < 0.01). The EUBCR sequential extraction procedure revealed that the acid extractable fractions of Cd, Cu, Pb and Zn decreased significantly (p < 0.05) with biochar addition. Rice straw biochar was more effective than bamboo biochar in decreasing the acid extractable metal fractions, and the effect was more pronounced with increasing biochar application rate. The effect of biochar particle size on extractable metal concentrations was not consistent. The 5% rice straw biochar treatment reduced the DTPA-extractable metal concentrations in the order of Cd < Cu < Pb < Zn, and reduced the acid extractable pool of Cd, Cu, Pb and Zn by 11, 17, 34 and 6%, respectively, compared to the control. In the same 5% rice straw biochar treatments, the organic bound fraction increased by 37, 58, 68 and 18% for Cd, Cu, Pb and Zn, respectively, compared to the control, indicating that the immobilized metals were mainly bound in the soil organic matter fraction. The results demonstrated that the rice straw biochar can effectively immobilize heavy metals, thereby reducing their mobility and bioavailability in contaminated soils. (C) 2016 Elsevier Ltd. All rights reserved.</P>

COMBUSTION VISUALIZATION AND EMISSIONS OF A DIRECT INJECTION COMPRESSION IGNITION ENGINE FUELED WITH BIO-DIESOHOL

LU X.,HUANG Z.,ZHANG W.,LI D. The Korean Society of Automotive Engineers 2005 International journal of automotive technology Vol.6 No.1

The purpose of this paper is to experimentally investigate the engine pollutant emissions and combustion characteristics of diesel engine fueled with ethanol-diesel blended fuel (bio-diesohol). The experiments were performed on a single-cylinder DI diesel engine. Two blend fuels were consisted of $15\%$ ethanol, $83.5\%$ diesel and $1.5\%$ solublizer (by volume) were evaluated: one without cetane improver (E15-D) and one with a cetane improver (E15-D+CN improver). The engine performance parameters and emissions including fuel consumption, exhaust temperature, lubricating oil temperature, Bosch smoke number, CO, NOx, and THC were measured, and compared to the baseline diesel fuel. In order to gain insight into the combustion characteristics of bio-diesohol blends, the engine combustion processes for blended fuels and diesel fuel were observed using an Engine Video System (AVL 513). The results showed that the brake specific fuel consumption (BSFC) increased at overall engine operating conditions, but it is worth noting that the brake thermal efficiency (BTE) increased by up to $1-2.3\%$ with two blends when compared to diesel fuel. It is found that the engine fueled with ethanol-diesel blend fuels has higher emissions of THC, lower emissions of CO, NOx, and smoke. And the results also indicated that the cetane improver has positive effects on CO and NOx emissions, but negative effect on THC emission. Based on engine combustion visualization, it is found that ignition delay increased, combustion duration and the luminosity of flame decreased for the diesohol blends. The combustion is improved when the CN improver was added to the blend fuel.

Emergence of room-temperature ferroelectricity at reduced dimensions

Lee, D.,Lu, H.,Gu, Y.,Choi, S.-Y.,Li, S.-D.,Ryu, S.,Paudel, T. R.,Song, K.,Mikheev, E.,Lee, S.,Stemmer, S.,Tenne, D. A.,Oh, S. H.,Tsymbal, E. Y.,Wu, X.,Chen, L.-Q.,Gruverman, A.,Eom, C. B. American Association for the Advancement of Scienc 2015 Science Vol.349 No.6254

<P><B>Thinning films induces ferroelectricity</B></P><P>Thin ferroelectric films are needed in computers and medical devices. However, traditional ferroelectric films typically become less and less polarized the thinner the films become. Instead of using a good ferroelectric and making it thinner, Lee <I>et al.</I> started with SrTiO<SUP>3</SUP>, which in its bulk form is not ferroelectric. This material does have naturally occurring nanosized polarized regions. and when the thickness of the SrTiO<SUB>3</SUB> films reaches the typical size of these regions, the whole film aligns and becomes ferroelectric.</P><P><I>Science</I>, this issue p. 1314</P><P>The enhancement of the functional properties of materials at reduced dimensions is crucial for continuous advancements in nanoelectronic applications. Here, we report that the scale reduction leads to the emergence of an important functional property, ferroelectricity, challenging the long-standing notion that ferroelectricity is inevitably suppressed at the scale of a few nanometers. A combination of theoretical calculations, electrical measurements, and structural analyses provides evidence of room-temperature ferroelectricity in strain-free epitaxial nanometer-thick films of otherwise nonferroelectric strontium titanate (SrTiO<SUB>3</SUB>). We show that electrically induced alignment of naturally existing polar nanoregions is responsible for the appearance of a stable net ferroelectric polarization in these films. This finding can be useful for the development of low-dimensional material systems with enhanced functional properties relevant to emerging nanoelectronic devices.</P>

Effect of Ca²⁺ on the activity and structure of α-glucosidase: Inhibition kinetics and molecular dynamics simulations

Zhang, X.,Shi, L.,Li, X.,Sheng, Q.,Yao, L.,Shen, D.,Lu, Z.R.,Zhou, H.M.,Park, Y.D.,Lee, J.,Zhang, Q. Society for Bioscience and Bioengineering, Japan ; 2014 Journal of bioscience and bioengineering Vol.117 No.6

Understanding the mechanism of inhibition of α-glucosidase (EC 3.2.1.20) is clinically important because of the involvement of this enzyme in type 2 diabetes mellitus. In this study, we conducted inhibition kinetics of α-glucosidase with Ca<SUP>2+</SUP> and 10-ns molecular dynamics simulations. We found that direct binding of Ca<SUP>2+</SUP> to the enzyme induced structural changes and inhibited enzyme activity. Ca<SUP>2+</SUP> inhibited α-glucosidase in a mixed-type reaction (K<SUB>i</SUB> = 27.0 +/- 2.0 mM) and directly induced the unfolding of α-glucosidase, which resulted in the exposure of hydrophobic residues. The simulations suggest that thirteen Ca<SUP>2+</SUP> ions may interact with α-glucosidase residues and that the Ca<SUP>2+</SUP> binding sites are associated with the structural changes in α-glucosidase. Our study provides insight into the mechanism of the Ca<SUP>2+</SUP>-induced structural changes in α-glucosidase and the inhibition of ligand binding. These results suggest that Ca<SUP>2+</SUP> could act as a potent inhibitor of α-glucosidase for the treatment of type 2 diabetes mellitus.