Sulphur reduction additive prepared from caustic-modified kaolin

Clay Minerals ◽  
2005 ◽  
Vol 40 (3) ◽  
pp. 311-316 ◽  
Author(s):  
Shu-Hong Sun ◽  
Shu-Qin Zheng ◽  
Zhi-Feng Wang ◽  
Yan-Hui Zhang ◽  
Jian-Tai Ma
Keyword(s):  
Acid Site ◽  
Mesoporous Structure ◽  
Site Characterization ◽  
Small Scale ◽  
X Ray Diffraction ◽  
Yield Distribution ◽  
X Ray ◽  
Fluid Bed ◽  
Sulphur Reduction

AbstractThe performance of a fluidized cracking catalyst additive prepared from caustic-modified kaolin microspheres for gasoline S reduction was investigated using N2 adsorption, infrared acid-site characterization, X-ray diffraction and small-scale fluid bed reactor tests. The additive exhibited improved coke selectivity and yield distribution, and the S content of cracked gasoline was reduced significantly. The results indicated that a reactive mesoporous structure was formed in the modified kaolin.

Solid-state Thermoelectric Characteristics of NiII, FeII, CoII, and CuII Borohydrides

2021 ◽  
Author(s):  
Isam M. Arafa ◽  
Mazin Y. Shatnawi ◽  
Yousef N. Obeidallah ◽  
Ahmed K. Hijazi ◽  
Yaser A . Yousef
Keyword(s):  
Energy Transport ◽  
Waste Heat ◽  
Mixed Valence ◽  
Small Scale ◽  
X Ray Diffraction ◽  
Promising Candidate ◽  
X Ray ◽  
Cold Pressed ◽  
Thermal Energy Transport ◽  
Body Heat

Abstract Four transition metal borohydrides (MTBHs, MT = Ni, Fe, Co, and Cu) were prepared by sonicating a mixture of the desired MT salt with excess NaBH4 in a nonaqueous DMF/CH3OH media. The process afforded bimetallic (Ni-BH4), trimetallic (Fe-BH4, Co-BH4), and mixed-valence (Cu-H, Cu-BH4) amorphous, ferromagnetic nanoparticles as identified by thermal, ATR-IR, X-Ray diffraction, and magnetic susceptibility techniques. The electrical conductivity (σ) of cold-pressed discs of these MTBHs shows a nonlinear increase while their thermal conductivity (κ) decreases in the temperature range of 303 ≤ T ≤ 373 K. The thermal energy transport occurs through phonon lattice dynamics rather than electronic. The σ/κ ratio shows a nonlinear steep increase from 9.4 to 270 KV-2 in Ni-BH4, while a moderate-weak increase is observed for Fe-BH4, Co-BH4, and Cu-BH4. Accordingly, the corresponding thermoelectric (TE) parameters S, PF, ZT, and η were evaluated. All TE data shows that the bimetallic Ni-BH4 (S, 80 μVK-1; PF, 259 μWm-1K-2; ZT 0.64; η, 2.56%) is a better TE semiconductor than the other three MT-BHs investigated in this study. Our findings show that Ni-BH4 is a promising candidate to exploit low-temperature waste heat from body heat, sunshine, and small domestic devices for small-scale TE applications.

Evolution of texture and internal stresses within polycrystalline rock salt using in situ 3D synchrotron computed tomography and 3D X-ray diffraction

2021 ◽  
Vol 54 (5) ◽  
pp. 1379-1393
Author(s):  
Amirsalar Moslehy ◽  
Khalid A. Alshibli ◽  
Timothy J. Truster ◽  
Peter Kenesei ◽  
Wadi H. Imseeh ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Slip System ◽  
Rock Salt ◽  
Small Scale ◽  
Internal Stresses ◽  
X Ray Diffraction ◽  
Crack Network ◽  
X Ray ◽  
Fully Connected

Rock salt caverns have been extensively used as reliable repositories for hazardous waste such as nuclear waste, oil or compressed gases. Undisturbed rock salt deposits in nature are usually impermeable and have very low porosity. However, rock salt formations under excavation stresses can develop crack networks, which increase their porosities; and in the case of a connected crack network within the media, rock salt may become permeable. Although the relationship between the permeability of rock salt and the applied stresses has been reported in the literature, a microscopic study that investigates the properties influencing this relationship, such as the evolution of texture and internal stresses, has yet to be conducted. This study employs in situ 3D synchrotron micro-computed tomography and 3D X-ray diffraction (3DXRD) on two small-scale polycrystalline rock salt specimens to investigate the evolution of the texture and internal stresses within the specimens. The 3DXRD technique measures the 3D crystal structure and lattice strains within rock salt grains. The specimens were prepared under 1D compression conditions and have shown an initial {111} preferred texture, a dominant {110}〈110〉 slip system and no fully connected crack network. The {111} preferred texture under the unconfined compression experiment became stronger, while the {111}〈110〉 slip system became more prominent. The specimens did not have a fully connected crack network until applied axial stresses reached about 30 MPa, at a point where the impermeability of the material becomes compromised due to the development of multiple major cracks.

scholarly journals Kinetic Control of Parallel versus Antiparallel Amyloid Aggregation via Shape of the Growing Aggregate

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Ali Asghar Hakami Zanjani ◽  
Nicholas P. Reynolds ◽  
Afang Zhang ◽  
Tanja Schilling ◽  
Raffaele Mezzenga ◽  
...  
Keyword(s):  
Self Assembly ◽  
Small Scale ◽  
Kinetic Control ◽  
Amyloid Aggregation ◽  
X Ray Diffraction ◽  
Human Lysozyme ◽  
X Ray ◽  
Contact Topology ◽  
Future Design ◽  
Assembly Pathways

Abstract By combining atomistic and higher-level modelling with solution X-ray diffraction we analyse self-assembly pathways for the IFQINS hexapeptide, a bio-relevant amyloid former derived from human lysozyme. We verify that (at least) two metastable polymorphic structures exist for this system which are substantially different at the atomistic scale, and compare the conditions under which they are kinetically accessible. We further examine the higher-level polymorphism for these systems at the nanometre to micrometre scales, which is manifested in kinetic differences and in shape differences between structures instead of or as well as differences in the small-scale contact topology. Any future design of structure based inhibitors of the IFQINS steric zipper, or of close homologues such as TFQINS which are likely to have similar structures, should take account of this polymorphic assembly.

Engineering Iron-Based Nanoparticles Spatially Dispersed on Mesoporous Carbon and Its Catalytic Activity for the Direct Oxidization of Benzene to Phenol

NANO ◽  
2018 ◽  
Vol 13 (08) ◽  
pp. 1850094
Author(s):  
Qiang Sun ◽  
Long Liu ◽  
Yi-Ding Li ◽  
Zeng-Rong Wang ◽  
Xue Zhang
Keyword(s):  
Mesoporous Carbon ◽  
Molecular Diffusion ◽  
Carbon Matrix ◽  
Mesoporous Structure ◽  
X Ray Diffraction ◽  
Efficient Catalyst ◽  
X Ray ◽  
Transmission Electron ◽  
Benzene Hydroxylation ◽  
Iron Based

We report engineered iron-based nanoparticles supported on cagelike mesoporous carbon that leaves its most mesopores empty to retain an open pore network and are expected to be efficient catalyst with fast molecular diffusion/transportation. The nano-scale iron-based particle inlayed in mesoporous carbon catalyst was obtained via the introduction of N atoms as an anchor. Results of X-ray diffraction, N2 sorption and transmission electron microscopy showed that the cagelike mesoporous structure of the carbon matrix was retained during catalyst preparation and iron-based nanoparticles were spatially dispersed on the mesoporous carbon. Importantly, it was found that the obtained iron-based nanoparticles inlayed into mesoporous carbon with a low Fe loading of 1.26[Formula: see text]wt.% was an appropriate catalyst for the benzene hydroxylation to phenol using H2O2 as the oxidant. At a low temperature of 30∘C, 19.4% conversion to benzene and 14.6% phenol yield were obtained; in addition, the catalyst could be recycled at least four times.

Crystallization Characteristics Of Phase Change Nanoparticle Arrays Fabricated By Self-Assembly Based Lithography

2008 ◽  
Vol 1072 ◽  
Author(s):  
Yuan Zhang ◽  
Simone Raoux ◽  
Daniel Krebs ◽  
Leslie E. Krupp ◽  
Teya Topuria ◽  
...  
Keyword(s):  
Phase Change ◽  
Self Assembly ◽  
Crystallization Behavior ◽  
Small Scale ◽  
Nanoparticle Arrays ◽  
X Ray Diffraction ◽  
Time Resolved ◽  
X Ray ◽  
Nanodot Arrays ◽  
Patterned Materials

ABSTRACTPhase change nanodot arrays were fabricated using self-assembly diblock copolymer template PS-b-PMMA (polystyrene-poly (methyl-methacrylate)) and studied by time resolved X-ray diffraction. The size of the nanodots was less than 15nm in diameter with 40nm spacing. This method is quite flexible regarding the patterned materials, and can be used on different substrates. The crystallization behavior of small scale phase change nanodot arrays was studied for different materials, such as Ge15Sb85, Ge2Sb2Te5 and Ag and In doped Sb2Te. It was found that the nanodots had higher crystallization temperatures compared to their corresponding blanket films and crystallized over a broader temperature range.

scholarly journals Materials identification using a small-scale pixellated x-ray diffraction system

2016 ◽  
Vol 49 (17) ◽  
pp. 175304 ◽  
Author(s):  
D O’Flynn ◽  
C Crews ◽  
I Drakos ◽  
C Christodoulou ◽  
M D Wilson ◽  
...  
Keyword(s):  
Small Scale ◽  
X Ray Diffraction ◽  
X Ray

Synthesis and Characterization of Polythiophene / SBA-15 Composite

2014 ◽  
Vol 968 ◽  
pp. 49-52
Author(s):  
Qin Qin Hou
Keyword(s):  
Thermogravimetric Analysis ◽  
Oxidative Polymerization ◽  
Mesoporous Structure ◽  
Synthesis And Characterization ◽  
Scan Electron Micrographs ◽  
X Ray Diffraction ◽  
Channel System ◽  
X Ray ◽  
Adsorption Desorption

A new nanocomposite, semiconducting polythiophene (PT) confined in mesoporous silica (SBA-15) was synthesized. PT was formed in the pores of SBA-15 by subsequent oxidative polymerization with FeCl3. Different techniques were used to characterize the nanocomposite formation. X-ray diffraction (XRD) and N2 adsorption/desorption analysis showed that the nanocomposite possesses mesoporous structure, and the residual pore volume of nanocomposite was significantly lower than that of pure empty SBA-15. Scan electron micrographs confirmed the presence of polythiophene inside pore channels of the host, and thermogravimetric analysis proved confinement effect in the channel system.

1-Amino-3-nitroguanidine (ANQ) in High-performance Ionic Energetic Materials

2012 ◽  
Vol 67 (6) ◽  
pp. 573-588 ◽  
Author(s):  
Niko Fischer ◽  
Thomas M. Klapötke ◽  
Jörg Stierstorfer
Keyword(s):  
Nitric Acid ◽  
Energetic Materials ◽  
Electrical Discharge ◽  
High Performance ◽  
Small Scale ◽  
Detonation Pressure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dsc Measurements ◽  
Explosive Performance

1-Amino-3-nitroguanidine (ANQ, 2) was synthesized via hydrazinolysis of nitroguanidine (1). An appropriate Lewis structure of ANQ is drawn based on VB calculations. Due to its basicity, it can be protonated by strong mineral acids or acidic heterocycles. In order to synthesize new energetic materials the nitrate (3) and perchlorate (4) salts of 1-amino-3-nitroguanidine were synthesized by protonation of 2 with 40% nitric acid and 60% perchloric acid, respectively. 5-Nitrimino-1,4H-tetrazole obtained by reacting 5-amino-1H-tetrazole with 100% HNO3 was used to synthesize the nitriminotetrazolate salt 5. Furthermore, the dinitramide salt 6 of 1-amino-3-nitroguanidine was synthesized by metathesis reaction of silver dinitramide and 1-amino-3-nitroguanidinium chloride. The dinitroguanidinate salt 7 was synthesized by protonation of 2 with 1,3-dinitroguanidine, which was prepared from nitroguanidine in anhydrous nitric acid/N2O5. All compounds were fully characterized by singlecrystal X-ray diffraction, vibrational spectroscopy (IR and Raman), multinuclear NMR spectroscopy, mass spectrometry, elemental analysis, and DSC measurements. The heats of formation of 2 - 7 were calculated using the atomization method based on CBS-4M enthalpies. With these values and the experimental (X-ray) densities several detonation parameters such as the detonation pressure, velocity, energy, and temperature were computed using the EXPLO5 code. In addition, the sensitivities towards impact, friction and electrical discharge were tested using the BAM drophammer, friction tester as well as a small-scale electrical discharge device. A Koenen test with 1-amino-3-nitroguanidinium nitrate (3) was carried out in order to evaluate its explosive performance and shipping classification.

scholarly journals Studi Material Tanah Longsor Akibat Gempa Lombok 2018

Teras Jurnal ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 235
Author(s):  
Muhammad Nurjati Hidayat
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Volcanic Eruptions ◽  
Silty Sand ◽  
Small Scale ◽  
X Ray Diffraction ◽  
Mineralogical Analysis ◽  
X Ray ◽  
The Impact ◽  
Scanning Electron

<p align="center"><strong>Abstrak</strong></p><p> </p><p class="11daftarpustaka">Pada umumnya, tanah longsor terjadi dengan skala yang kecil dan dampak yang dihasilkan tidak parah sebagaimana letusan gunung berapi, gempa atau tsunami. Namun, perhatian terhadap bencana ini seringkali diabaikan oleh masyarakat dan perencanaan pembangunan kota. Ada beberapa faktor yang perlu diperhatikan dalam meneliti tanah longor, salah satunya adalah mineral tanah. Dalam studi ini, sampel tanah diambil dari Lombok Utara akibat dari gempa Lombok 2018. Penelitian ini dilakukan dengan mengelompokkan tanah berdasarkan USCS dan AASTHO, kemudian dilanjutkan dengan analisis mineralogi menggunakan XRD (X-Ray Diffraction) dan SEM (Scanning Electron Microscope). Berdasarkan klasifikasi USCS, tanah termasuk kategori pasir berlanau dan campuran lanau (SM); dan lempung anorganik dengan plastisitas rendah sampai sedang, lempung berkerikil, lempung berpasir, lempung berlanau, lempung kurus (lean clays). Pada klasifikasi AASHTOO, hasilnya adalah tanah berlanau (A-4); kerikil dan pasir yang berlanau atau berlempung (A-2-4); dan pasir halus (A-3). Berdasarkan hasil mineralogi menggunakan XRD dan SEM, material utama pada sampel tanah adalah Albite Calcian, Microline and Kuarsa.</p><p class="11daftarpustaka"> </p><p class="11daftarpustaka">Kata kunci: <em>longsor,</em><em> mineralogi, XRD, SEM</em><em></em></p><p align="center"><strong> </strong></p><p align="center"><strong> </strong></p><p align="center"><strong>Abstract</strong></p><p class="11daftarpustaka"> </p><p class="11daftarpustaka">Landslides generally occur on a small scale and the impact is not as severe as volcanic eruptions, earthquakes, or tsunamis. However, attention to these disasters is often ignored by the community and city development planning. In assessing the factors causing landslides there are many factors that need to be considered, one of which is soil minerals. The samples of soil in this study were taken from North Lombok as a result of the 2018 earthquake. This research is conducted by classifying the soil based on USCS and AASHTO, then proceed with mineralogical analysis using XRD (X-Ray Diffraction) and SEM (Scanning Electron Microscope). Based on USCS classification, the result of the analysis shows that soil samples have a classification of silty sand, and silt mixtures (SM); and inorganic clays or low to medium plasticity, gravelly clays, sandy clays, silty clays, lean clays (CL). For AASHTO classification, the result shows the sample belong to silty soil (A-4), silty or clayey gravel sand (A-2-4) and fine sand (A-3). Based on the results of mineralogical analysis using XRD and SEM, it is known that the dominant minerals making up the soil in the sample are Albite Calcian, Microline and Quartz</p><p class="11daftarpustaka"> </p><p class="11daftarpustaka">Keywords: <em>landslide, mineralogy, XRD, SEM</em><em></em></p><em></em><em></em>

Investigation of the Stress Fields Around a Fatigue Crack in Aluminium Alloy 5091

2008 ◽  
Vol 571-572 ◽  
pp. 119-124 ◽  
Author(s):  
M. Rahman ◽  
Michael E. Fitzpatrick ◽  
Lyndon Edwards ◽  
S. Pratihar ◽  
Matthew J. Peel ◽  
...  
Keyword(s):  
Fatigue Crack ◽  
Aluminium Alloy ◽  
Crack Tip ◽  
Fatigue Loading ◽  
Compact Tension ◽  
European Synchrotron Radiation Facility ◽  
Stress Fields ◽  
Small Scale ◽  
X Ray Diffraction ◽  
X Ray

There have been many theoretical studies to predict the stress fields around the tip of a growing fatigue crack. However, until recently the highly-localized, small scale nature of the stresses has meant that direct measurement has not been possible. With the current generation of synchrotron X-ray sources, sub-millimetre sampling dimensions are now possible, and it has become possible to evaluate directly the stresses at the tip of a fatigue crack and to see how the stresses evolve as the result of an overload, for example. In this paper we present results of synchrotron X-ray diffraction analysis of the stress fields around a fatigue crack in aluminium alloy 5091 (Al-Mg-Li-C-O); this is a dispersion-strengthened alloy with a fine grain size, which makes it ideal for such experiments. Compact tension (CT) specimens were prepared with constant amplitude fatigue loading. The energy dispersive X-ray diffraction (EDXRD) technique was used for measuring strains around the crack tip along the mid thickness of the specimen under in-situ loading. The measurement was carried out at the ESRF (European Synchrotron Radiation Facility), Grenoble, France on the ID15A beam line. The experimental crack tip stresses have been compared with the analytical fracture mechanics solution.

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