Biochar derived from Salvadora persica branches biomass as low-cost adsorbent for removal of uranium(VI) and thorium(IV) from water

Author(s):  
Mohammad Albayari ◽  
Mazen K. Nazal ◽  
Fawwaz I. Khalili ◽  
Norazzizi Nordin ◽  
Rohana Adnan
Keyword(s):  
Low Cost ◽  
2012 ◽  
Vol 14 (4) ◽  
pp. 700-711 ◽  
Author(s):  
I.A. Freires ◽  
I.C.G. Silva ◽  
L.A. Alves ◽  
L.M.D. Bezerra ◽  
R.D. Castro

Natural products have emerged as an effective and low-cost alternative for treating various diseases of the oral cavity. This study aimed to evaluate, through a systematic literature review, if there is scientific evidence ensuring the safe and effective use of natural product(s)-containing mouthwashes as adjunctive treatment of biofilm-induced gingivitis. Searches were conducted in the databases Medline, SciELO, LILACS and Cochrane Library, by using combinations of the key words gingivitis/natural products/phytotherapy/mouthwash, in English, Portuguese and Spanish. Studies published until September 2010 were considered. Four examiners analyzed independently: study design and phase, methodological quality (Jadad scale - JE), experimental product and its concentration, dosing interval and time of usage, as well as employed statistical analysis and clinical outcome of interest. From the 503 articles found, 08 were included in the final review as phase II, controlled, randomized and blind clinical trials, scoring 4 (25%) and 5 (75%) in JE. The main natural products assessed were: Azadirachta indica, Garcinia mangostana, Lippia sidoides, Salvadora persica and Sesamum indicum whose concentration, dosing interval, time of usage and adverse effects varied according to each study. The Plaque and Gingival Index were most employed, as well as α = 5% and paired t, Student's t, Wilcoxon and Mann-Whitney tests. A total of 62.5% and 50% of the products significantly reduced supragingival biofilm and gingivitis, respectively. Mouthwashes containing the essential oil from the leaves of L. sidoides (1%) and the extract from the leaves of A. indica (25%) can be indicated as adjunctive treatment of biofilm-induced gingivitis.


Crystals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 441 ◽  
Author(s):  
Fahad A. Alharthi ◽  
Abdulaziz Ali Alghamdi ◽  
Asma A. Alothman ◽  
Zainab M. Almarhoon ◽  
Munairah F. Alsulaiman ◽  
...  

Various ZnO nanomaterials such as nanorods, nanoparticles, and nanosheets were synthesized using Salvadora persica leaf extract via the sol–gel method. The prepared nanomaterials possess a large number of nanocavities. The synthesized nanomaterials were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), UV-visible diffuse reflectance studies (UV-DRS), scanning electron microscopy (SEM), and high resolution transmission electron microscopy (HT-TEM), and these nanomaterials were used to test photocatalytic applications for the degradation of highly hazardous methylene blue dye. The degradation efficiency was higher for materials with nanorods and nanosheets with nanocavities; this was due to the presence of the nanocavities, which made the catalyst more sensitive to light absorption. This method offers a green synthesis of different nanomaterials in bulk quantity at low cost.


Author(s):  
Y. L. Chen ◽  
S. Fujlshiro

Metastable beta titanium alloys have been known to have numerous advantages such as cold formability, high strength, good fracture resistance, deep hardenability, and cost effectiveness. Very high strength is obtainable by precipitation of the hexagonal alpha phase in a bcc beta matrix in these alloys. Precipitation hardening in the metastable beta alloys may also result from the formation of transition phases such as omega phase. Ti-15-3 (Ti-15V- 3Cr-3Al-3Sn) has been developed recently by TIMET and USAF for low cost sheet metal applications. The purpose of the present study was to examine the aging characteristics in this alloy.The composition of the as-received material is: 14.7 V, 3.14 Cr, 3.05 Al, 2.26 Sn, and 0.145 Fe. The beta transus temperature as determined by optical metallographic method was about 770°C. Specimen coupons were prepared from a mill-annealed 1.2 mm thick sheet, and solution treated at 827°C for 2 hr in argon, then water quenched. Aging was also done in argon at temperatures ranging from 316 to 616°C for various times.


Author(s):  
J. D. Muzzy ◽  
R. D. Hester ◽  
J. L. Hubbard

Polyethylene is one of the most important plastics produced today because of its good physical properties, ease of fabrication and low cost. Studies to improve the properties of polyethylene are leading to an understanding of its crystalline morphology. Polyethylene crystallized by evaporation from dilute solutions consists of thin crystals called lamellae. The polyethylene molecules are parallel to the thickness of the lamellae and are folded since the thickness of the lamellae is much less than the molecular length. This lamellar texture persists in less perfect form in polyethylene crystallized from the melt.Morphological studies of melt crystallized polyethylene have been limited due to the difficulty of isolating the microstructure from the bulk specimen without destroying or deforming it.


Author(s):  
J. Temple Black

In ultramicrotomy, the two basic tool materials are glass and diamond. Glass because of its low cost and ease of manufacture of the knife itself is still widely used despite the superiority of diamond knives in many applications. Both kinds of knives produce plastic deformation in the microtomed section due to the nature of the cutting process and microscopic chips in the edge of the knife. Because glass has no well defined slip planes in its structure (it's an amorphous material), it is very strong and essentially never fails in compression. However, surface flaws produce stress concentrations which reduce the strength of glass to 10,000 to 20,000 psi from its theoretical or flaw free values of 1 to 2 million psi. While the microchips in the edge of the glass or diamond knife are generally too small to be observed in the SEM, the second common type of defect can be identified. This is the striations (also termed the check marks or feathers) which are always present over the entire edge of a glass knife regardless of whether or not they are visable under optical inspection. These steps in the cutting edge can be observed in the SEM by proper preparation of carefully broken knives and orientation of the knife, with respect to the scanning beam.


Author(s):  
H. O. Colijn

Many labs today wish to transfer data between their EDS systems and their existing PCs and minicomputers. Our lab has implemented SpectraPlot, a low- cost PC-based system to allow offline examination and plotting of spectra. We adopted this system in order to make more efficient use of our microscopes and EDS consoles, to provide hardcopy output for an older EDS system, and to allow students to access their data after leaving the university.As shown in Fig. 1, we have three EDS systems (one of which is located in another building) which can store data on 8 inch RT-11 floppy disks. We transfer data from these systems to a DEC MINC computer using “SneakerNet”, which consists of putting on a pair of sneakers and running down the hall. We then use the Hermit file transfer program to download the data files with error checking from the MINC to the PC.


Author(s):  
T. P. Nolan

Thin film magnetic media are being used as low cost, high density forms of information storage. The development of this technology requires the study, at the sub-micron level, of morphological, crystallographic, and magnetic properties, throughout the depth of the deposited films. As the microstructure becomes increasingly fine, widi grain sizes approaching 100Å, the unique characterization capabilities of transmission electron microscopy (TEM) have become indispensable to the analysis of such thin film magnetic media.Films were deposited at 225°C, on two NiP plated Al substrates, one polished, and one circumferentially textured with a mean roughness of 55Å. Three layers, a 750Å chromium underlayer, a 600Å layer of magnetic alloy of composition Co84Cr14Ta2, and a 300Å amorphous carbon overcoat were then sputter deposited using a dc magnetron system at a power of 1kW, in a chamber evacuated below 10-6 torr and filled to 12μm Ar pressure. The textured medium is presently used in industry owing to its high coercivity, Hc, and relatively low noise. One important feature is that the coercivity in the circumferential read/write direction is significandy higher than that in the radial direction.


Author(s):  
K.M. Hones ◽  
P. Sheldon ◽  
B.G. Yacobi ◽  
A. Mason

There is increasing interest in growing epitaxial GaAs on Si substrates. Such a device structure would allow low-cost substrates to be used for high-efficiency cascade- junction solar cells. However, high-defect densities may result from the large lattice mismatch (∼4%) between the GaAs epilayer and the silicon substrate. These defects can act as nonradiative recombination centers that can degrade the optical and electrical properties of the epitaxially grown GaAs. For this reason, it is important to optimize epilayer growth conditions in order to minimize resulting dislocation densities. The purpose of this paper is to provide an indication of the quality of the epitaxially grown GaAs layers by using transmission electron microscopy (TEM) to examine dislocation type and density as a function of various growth conditions. In this study an intermediate Ge layer was used to avoid nucleation difficulties observed for GaAs growth directly on Si substrates. GaAs/Ge epilayers were grown by molecular beam epitaxy (MBE) on Si substrates in a manner similar to that described previously.


Author(s):  
R.J. Mount ◽  
R.V. Harrison

The sensory end organ of the ear, the organ of Corti, rests on a thin basilar membrane which lies between the bone of the central modiolus and the bony wall of the cochlea. In vivo, the organ of Corti is protected by the bony wall which totally surrounds it. In order to examine the sensory epithelium by scanning electron microscopy it is necessary to dissect away the protective bone and expose the region of interest (Fig. 1). This leaves the fragile organ of Corti susceptible to physical damage during subsequent handling. In our laboratory cochlear specimens, after dissection, are routinely prepared by the O-T- O-T-O technique, critical point dried and then lightly sputter coated with gold. This processing involves considerable specimen handling including several hours on a rotator during which the organ of Corti is at risk of being physically damaged. The following procedure uses low cost, readily available materials to hold the specimen during processing ,preventing physical damage while allowing an unhindered exchange of fluids.Following fixation, the cochlea is dehydrated to 70% ethanol then dissected under ethanol to prevent air drying. The holder is prepared by punching a hole in the flexible snap cap of a Wheaton vial with a paper hole punch. A small amount of two component epoxy putty is well mixed then pushed through the hole in the cap. The putty on the inner cap is formed into a “cup” to hold the specimen (Fig. 2), the putty on the outside is smoothed into a “button” to give good attachment even when the cap is flexed during handling (Fig. 3). The cap is submerged in the 70% ethanol, the bone at the base of the cochlea is seated into the cup and the sides of the cup squeezed with forceps to grip it (Fig.4). Several types of epoxy putty have been tried, most are either soluble in ethanol to some degree or do not set in ethanol. The only putty we find successful is “DUROtm MASTERMENDtm Epoxy Extra Strength Ribbon” (Loctite Corp., Cleveland, Ohio), this is a blue and yellow ribbon which is kneaded to form a green putty, it is available at many hardware stores.


Author(s):  
Shaohua Lu ◽  
Weidong Hu ◽  
Xiaojun Hu

Due to their low cost and improved safety compared to lithium-ion batteries, sodium-ion batteries have attracted worldwide attention in recent decades.


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