Crystal Arrangement Research Articles

Structure determination and Hirshfeld surface analysis of new cocrystal and salt forms of 5-aminotetrazole with hydroxy- and nitro-substituted carboxylic acids.

Two new crystalline solids, namely, 5-aminotetrazole-3,5-dihydroxybenzoic acid-water (1/4/6), CH3N5·4C7H6O4·6H2O (I), and 5-aminotetrazolium 3,5-dinitrosalicylate, CH4N5+·C7H3N2O7- (II), have been synthesized and characterized by single-crystal X-ray diffraction and Hirshfeld surface analysis. The crystal packing arrangements of I and II are governed by N-H...O and O-H...O hydrogen-bonding interactions. In cocrystal I, adjacent acid molecules are linked through O-H...O hydrogen bonds, forming a dimer with an R22(8) motif. In salt II, the tetrazolium cation and acid anion are linked through N-H...O hydrogen bonds to also form a dimer with an R22(8) motif. Further N-H...O and O-H...O hydrogen bonds help to stabilize the crystal packing, along with aromatic π-π stacking interactions in I and carbonyl...π interactions in II. The Hirshfeld surface analysis and fingerprint plots reveal that O...H/H...O interactions contribute 34.4% of the total interactions in the crystal packing of cocrystal I and 36.7% in salt II.

Structure-property relations of a unique and systematic dataset of 19 isostructural multicomponent apremilast forms.

The structure-property relations are examined for apremilast cocrystals and solvates in this work. A unique and large dataset of multicomponent crystal forms is presented including 7 cocrystals and 12 solvates. In total, 15 of the presented multicomponent forms and their crystal structures are published here for the first time. This dataset is unique owing to the extreme crystal packing similarity of all 19 crystal forms. This fact makes the evaluation of structure-property relations significantly easier and more precise since the differences in the crystal lattice arrangement are close to negligible. Properties of the guest molecules used here can be directly correlated with the macroscopic properties of the corresponding multicomponent forms. Interestingly, a considerable correlation was found between the intrinsic dissolution rate of the multicomponent forms and their solubility, as well as the solubility of their guest molecules in the dissolution medium. The latter is of particular interest as it can aid in the design of multicomponent forms with tuned properties.

Dynamic Circularly Polarized Luminescence with Tunable Handedness and Intensity Enabled by Achiral Dichroic Dyes in Cholesteric Liquid Crystal Medium.

Cholesteric liquid crystals (CLCs) are chiral supramolecular systems that self-assemble into a highly regular helical arrangement in a liquid crystal (LC) medium. Such an arrangement is highly beneficial for the chiral enlargement effect on circularly polarized luminescence (CPL) signals. Dichroic dyes with rod-like molecular structures can exhibit fluorescence anisotropy along both the long and short molecular axes owing to their transition dipole moment (TDM) vectors. In this work, a pair of donor-accepter (D-A) achiral dichroic dyes is prepared, namely, 3,4-ethylenedioxythiophene derivative (P1, whose TDM vector is parallel to the long axis of the molecule, i.e., F|| > F⊥ ) and anthraquinone derivative (N1, whose TDM vector is perpendicular to the long axis of the molecule, i.e., F|| < F⊥ ). CLCs can be fabricated by doping P1 or N1 together with chiral 1,1'-binaphthyl-derived inducers into SLC1717 medium. Dynamic CPL with tunable handedness and intensity is achieved by changing the N1:P1 mass ratio, and the luminescence dissymmetry factor (gem ) value reaches |0.71|. This work describes the first observation of dynamic CPL with tunable handedness and intensity enabled by TDM regulation of achiral dichroic dyes in a CLC medium.

Cross-Scale Simulation Research on the Macro/Microstructure of TC4 Alloy Wire Laser Additive Manufacturing

A cross-scale model of macro-micro coupling is established for the wire laser additive manufacturing process of the TC4 titanium alloy. The model reproduces the dynamic evolution process of the molten pool shape, reveals the temperature change law in the molten pool, and simulates the microstructure and morphology of different regions of the molten pool. Finally, the model is used to quantitatively analyze the effects of process parameters (laser power, scanning speed) on the growth morphology of dendrites during solidification. The research shows that with the increase in laser power and the decrease in scanning speed, the peak temperature of the molten pool increases rapidly, and the size of the molten pool increases gradually. When the laser scanning speed is greater than 5 mm/s, the molten pool length decreases significantly. After solidification, an asymmetrically distributed equiaxed grain structure is formed at the upper part of the molten pool, the bottom of the molten pool is made up of slender columnar crystals, and the columnar-to-equiaxed transition (CET) occurs in the middle of the molten pool. With the decrease in laser power and the increase in scanning speed, the growth rate of dendrites becomes faster, the arm spacing and the overall morphology of dendrites become smaller, and the arrangement of columnar crystals have a tighter microstructure.

A Polarized Raman Spectroscopic Method for Advanced Analyses of the Osteon Lamellar Structure of Human Bone.

Raman spectroscopy has recently been used for quantitative analyses of cortical bone tissue and related materials, such as dentin and enamel. While those analyses have proven useful as potential diagnostic tools, the Raman spectrum of bone encrypts a wealth of additional molecular scale details about structure and crystal arrangement, which are yet to be unfolded. Such details directly link to both bone physiology and pathology. In this work, a triple monochromator spectrometer with high spectral resolution, employed in polarized light configurations, was used to extract quantitative details about the preferential crystallographic orientation of apatite and collagen components in a human proximal femoral cortical bone sample. This body of information was then used to model the bone structure at the nanometric scale through a methodology that could be key in assessments of bone structure in health and disease.

Characterizations of Single-Crystal Lithium Niobate Thin Films

Single-crystal lithium niobate thin films (lithium niobate on insulator, LNOI) are becoming a new material platform for integrating photonics. Investigation into the physical properties of LNOI is important for the design and fabrication of photonic devices. Herein, LNOIs were prepared by two methods: ion implantation and wafer bonding; and wafer bonding and grinding. High-resolution X-ray diffraction (HRXRD) and confocal Raman spectroscopy were used to study the LNOI lattice properties. The full-width at half-maximum (FWHM) of HRXRD and Raman spectra showed a regular crystal lattice arrangement of the LNOIs. The domain inversion voltage and electro-optical coefficient of the LNOIs were close to those of LN bulk material. This study provides useful information for LNOI fabrication and for photonic devices in LNOI.

Silver nanoprism-mediated protein estimation—an ultrasensitive platform for rapid estimation of protein concentration

Estimation of protein concentration in the range of nanogram level (ng/ml) is a big challenge for conventional protein estimation methods. The highly dipole sensitive spectroscopic properties of Silver nanoprism (AgNPR) has been utilized to develop a rapid and highly sensitive method for the estimation of globular protein concentration at ng/ml (or ppb) range. We have applied a unique molecular doping approach to introduce protein in the interstitial space of the Ag fcc(111) crystal planes within AgNPR structure. The presence of the doped protein induces deformation in the crystal plane arrangement of AgNPR that results in a quantitative red shift of the dipole resonance peak (D-peak) of AgNPR under UV–vis spectroscopy. The proposed method allows detection of a protein concentration range of as low as 1–20 ng ml−1- that is better than the sensitivity limit of conventional protein estimation techniques. This method has been successfully applied for commonly used proteins like haemoglobin (Hb), Bovine serum albumin (BSA), Trypsin (TRYP) and Lysozyme (LYS) with a very low limit of detection (LOD) within 2–6 ng ml−1. The lowest LOD value was shown by Hb as 2.08 ng ml−1. The method has further been validated by measuring Casein concentration from milk with an accuracy of 99% and 95% recovery for the concentration of 3.1 and 31 ng ml−1 respectively. Transmission emission microscopy (TEM) images show that the doped protein has been found to alter the size and shape of the AgNPR as a function of the dopant concentration by creating systematic deformation. This method does not require any alteration of the reaction temperature and solely depends on the physical interaction of doped protein with its neighbouring crystal structure of the nanoplanar geometry.

PEGylated aceclofenac solid lipid microparticles homolipid-based solidified reverse micellar solutions for drug delivery

Aceclofenac is a non-steroidal anti-inflammatory drug with poor aqueous solubility and a short half-life resulting in low bioavailability. Aceclofenac-loaded solid lipid microparticles based solidified reverse micellar solution (SLMs-SRMS) for oral drug delivery was investigated to improve the bioavailability and control drug release. Hot homogenization method was adopted to prepare the SLMs using a homolipid irvingia fat and Phospholipon® 90H with or without propylene glycol 6000 (PEGylation) in different ratios and characterized in vitro. The in vivo anti-inflammatory activity of the drug was determined on mice inflamed with carrageenan as phlogistic agent. Results showed that the morphology and particle sizes of the SLMs were spherical and smooth and ranged between 5.24 ± 0.01–97.44 ± 0.18 μm. EE % ranged between 67 - 81 %. A significant (p < 0.05) viscosity of 490 mPasec-1 was obtained. FTIR spectra indicated compatibility amongst the constituents. DSC showed a broad peak which depicted an imperfect matrix resulting in a deformation of crystal arrangement creating many spaces for drug entrapment. Delayed drug release was observed in almost all the formulations in SIF (pH, 6.8). Anti-inflammatory activity showed a significant inhibitory effect (p < 0.05, up to 90 %). Hence, the aceclofenac-loaded SLMs-SRMS showed desirable characteristics and could be used for controlled delivery of aceclofenac and thus alternative to conventional aceclofenac oral formulation.

Physico-chemical and biological responses for hydroxyapatite/ZnO/graphene oxide nanocomposite for biomedical utilization

Bioceramics, graphene oxide, and metal oxide-based biomaterials are intriguing prospects for hard tissue biomedical applications. Combining hydroxyapatite (HAP), graphene oxide (GO), and Zinc oxide (ZnO) to fabricate HAP/ZnO/GO nanocomposite presented a noticeable improvement in bioactivity biocompatibility and antimicrobial activity. The crystal lattice changes and structural arrangement of these nanocomposites are examined using XRD, TEM, and SEM. Moreover, the GO nanosheets, HAP, and ZnO bonding are reported in FTIR and XPS spectra. The TEM micrographs showed the nanocomposite structural alteration and revealed the uniformity of HAP and ZnO distribution into GO nanosheets with 10 nm in diameter and length of 25 nm. Furthermore, the SEM scan explained the porosity and integrated structure that showed a size of 0.3–1.4 μm. HAP/ZnO/GO roughness average reached 40.2 nm. The cell viability test for the nanocomposite revealed a high value of 99.5 ± 1.5%. The antibacterial property of HAP/ZnO/GO was confirmed with the reported inhibition zone of 20.4 ± 1 mm and 15.3 ± 1.1 mm against E. coli and S. aureus. Herein, combining HAP and ZnO with GO nanosheets alters morphological features and enhances roughness parameters of the fabricated nanocomposite. Besides structural porosity, cell adhesion and bioactivity improved. The resulting porous reinforced nanocomposite that showed excellent antibacterial activity is a biomaterial of interest in bone replacement utilization.

Synthesis, Characterization, and Assessment of Anti-Cancer Potential of ZnO Nanoparticles in an In Vitro Model of Breast Cancer.

Advanced innovations for combating variants of aggressive breast cancer and overcoming drug resistance are desired. In cancer treatment, ZnO nanoparticles (NPs) have the capacity to specifically and compellingly activate apoptosis of cancer cells. There is also a pressing need to develop innovative anti-cancer therapeutics, and recent research suggests that ZnO nanoparticles hold great potential. Here, the in vitro chemical effectiveness of ZnO NPs has been tested. Zinc oxide (ZnO) nanoparticles were synthesized using Citrullus colocynthis (L.) Schrad by green methods approach. The generated ZnO was observed to have a hexagonal wurtzite crystal arrangement. The generated nanomaterials were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), UV-visible spectroscopy. The crystallinity of ZnO was reported to be in the range 50–60 nm. The NPs morphology showed a strong absorbance at 374 nm with an estimated gap band of 3.20 eV to 3.32 eV. Microscopy analysis proved the morphology and distribution of the generated nanoparticles to be around 50 nm, with the elemental studies showing the elemental composition of ZnO and further confirming the purity of ZnO NPs. The cytotoxic effect of ZnO NPs was evaluated against wild-type and doxorubicin-resistant MCF-7 and MDA-MB-231 breast cancer cell lines. The results showed the ability of ZnO NPs to inhibit the prefoliation of MCF-7 and MDA-MB-231 prefoliation through the induction of apoptosis without significant differences in both wild-type and resistance to doxorubicin.

Harvester wheel energy (type 4)

Since the advent of modern civilization, humans have always been depended upon the fossil fuels as the source of energy for their daily requirements. With the exponential growth in the population, the dependence on these conventional sources for the daily energy requirements has led to the depletion of the same and adverse ill-effects on the environment. To lessen the burden and if possible, minimize to zero, energy harvesting has become the need of the hour and the development of the different energy harvesting technologies has been the prime area of research. Of them, piezoelectric materials have gained the popularity in this niche of energy harvesting solutions and have resulted in promising possibilities of efficient tapping of waste energy for future use. In this paper, a technique of application of piezoelectric material for harnessing energy i.e., along the circumference of the inner lining of the tire and rough calculations has been made to project the probable energy tapped and its usage. The current work describes a sample arrangement of crystal and various new arrangements based on maximum power output can be made.

Strain-Assisted Single Pt Sites on High-Curvature MoS 2 Surface for Ultrasensitive H 2 S Sensing

Strain-Assisted Single Pt Sites on High-Curvature MoS ₂ Surface for Ultrasensitive H ₂ S Sensing

Unique Periodic Rings Composed of Fractal-Growth Dendritic Branching in Poly(p-dioxanone).

Amorphous poly(p-vinyl phenol) (PVPh) was added into semicrystalline poly(p-dioxanone) (PPDO) to induce a uniquely novel dendritic/ringed morphology. Polarized-light optical, atomic-force and scanning electron microscopy (POM, AFM, and SEM) techniques were used to observe the crystal arrangement of a uniquely peculiar cactus-like dendritic PPDO spherulite, with periodic ring bands not continuingly circular such as those conventional types reported in the literature, but discrete and detached to self-assemble on each of the branches of the lobs. Correlations and responsible mechanisms for the formation of this peculiar banded-dendritic structure were analyzed. The periodic bands on the top surface and interior of each of the cactus-like lobs were discussed. The banded pattern was composed of feather-like lamellae in random fractals alternately varying their orientations from the radial direction to the tangential one. The tail ends of lamellae at the growth front spawned nucleation cites for new branches; in cycles, the feather-like lamellae self-divided into multiple branches following the Fibonacci sequence to fill the ever-expanding space with the increase of the radius. The branching fractals in the sequence and the periodic ring-banded assembly on each of the segregated lobs of cactus-like dendrites were the key characteristics leading to the formation of this unique dendritic/ringed PPDO spherulite.

Facile fabrication of novel ceria-based nanocomposite (CYO-CSO) via co-precipitation: Electrochemical, photocatalytic and antibacterial performances

Ceria-based mixed metal oxide (rare-earth-based) nanocomposites have become well-known and play an important part in contemporary nanotechnology research due to their superior photocatalytic, biological, and electrochemical performance. A Ce0.8Y0.2 O2-δ–Ce0.8Sm0.2O2-δ (CYO-CSO) nanocomposite was fabricated utilizing a chemical precipitation technique for a variety of applications. For structural study, Fourier transfer infrared (FT-IR) spectroscopy, X-ray powder diffraction (XRD), and thermographic analysis (TGA) were used, as well as Scanning Electronic microscopy (SEM) and Energy dispersive X-ray analysis (EDX) for morphological and elemental analysis. There was no secondary phase seen during the creation of fluorite cubic crystal arrangement. XRD and FTIR were used to reveal the metal-oxygen connection. UV–Vis spectroscopy was used to calculate the optical bandgap of the produced nanocomposite. Electrochemical characteristics were discovered when conducting electrochemical impedance studies (EIS) at a frequency range of 40 Hz to 6 kHz and a voltage of 1.3 V. Methylene blue (MB) was utilized to estimate photocatalytic performance. The photocatalytic performance of CYO-CSO nanocomposite for MB dye was shown to be superior (93%). The antibacterial characteristic features of the synthesized CYO-CSO nanocomposite against foodborne pathogens are satisfactory.

Growth, crystal structure, Hirshfeld surface and vibrational properties of a new supramolecular hybrid material: (C4H7N2)2TeBr6

A novel tellurium (IV) hybrid compound with 2-methylimidazole was prepared. The crystal was grown by slow evaporation method from aqueous solutions at room temperature giving birth to a new compound with formula (C4H7N2)2TeBr6. The structure was determined by single-crystal X-ray diffraction. It crystallizes in the monoclinic system, space group C 2/c, with the following parameters: a = 18.577(2)Å, b = 9.1497(10)Å, c = 13.5355(17)Å, α = 90°, β = 123.835(5)°, γ = 90° and Z = 8. The structure was solved with a final R = 0.044 for 2783 independent reflections. The crystal arrangement consists of [TeBr6]2− anions surrounded by [C4H7N2]2+ cations. The stability of the structure was ensured by hydrogen bonding contacts (N–H…Br) lengths that are in the range of 3.490–3.682 Å. The infrared spectra (FTIR) were recorded in the 4000–550 cm−1, confirming the existence of vibrational modes that correspond to the organic and inorganic groups. The crystal packing was stabilized mainly by Br…H (73.6%) interactions. Hirshfeld surface calculations were conducted to further investigate intermolecular interactions, associated 2D fingerprint plots and enrichment ratio, revealing the quantitatively relative contribution of these interactions in the crystal packing.

Mechanically flexible multi-stacked ITO/PEDOT:PSS hybrid superlattice films for transparent conductive electrodes

To improve the flexibility of transparent conductive electrodes (TCEs), we designed multi-stacked ITO/PEDOT:PSS hybrid superlattice (IxPy) films for flexible polymer-dispersed liquid crystal (PDLC), foldable thin-film heaters (TFHs), and flexible perovskite solar cells (PSCs). The electrical and optical properties of the multi-stacked IxPy films were examined and then optimized at the I6P5 film (ITO: 6 layers and PEDOT: 5 layers). The I6P5 film showed a sheet resistance of 149.66 Ohm/square, high transmittance of 93.75% at the visible range of (400–800) nm, and achieved the highest figure-of-merit (FOM) value of 3.50 × 10−3, compared with the other stacked conditions. Furthermore, the I6P5 films showed better flexibility by suppressing the brittle nature of ITO through inserting very thin PEDOT:PSS. The I6P5 film as an electrode was employed as a flexible PDLC, flexible TFHs, and flexible PSCs. The I6P5-based PDLC showed a clear distinction between on-state and off-state. At the applied voltage of 60 V, the transmittance of PDLC increased to 48.829% because of the arrangement of liquid crystals in the current direction. The flexible TFHs with I6P5 superlattice electrode showed high saturation temperature of above 100 °C at 14 V. Moreover, the I6P5 electrodes showed similar efficiency to reference ITO films in flexible PSCs. These results indicate that the multi-stacked IxPy hybrid superlattice films offer superior potential as highly transparent and foldable or flexible conductive electrodes.

The South American dipnoan Metaceratodus baibianorum (Dipnoi, Ceratodontidae) from the Upper Cretaceous La Colonia Formation, Patagonia, Argentina: an approach from the histology of the tooth plates

Lungfish remains are a frequent component of the Upper Cretaceous deposits of Patagonia; they are mainly represented by tooth plates fused or not to the jaw bones. Here, we describe the histology of the tooth plates of Metaceratodus baibianorum from the La Colonia Formation, Patagonia. The present study is the first of its kind to be carried out in Argentinian dipnoans. Under the petrographic microscope, the tooth plates show two distinct arrangements of calcium hydroxyapatite crystals in the interdenteonal dentine (cross birefringent pattern and monorefringent pattern), which differ from the one present in the circumdenteonal dentine (lamellar birefringent pattern). The tissue arrangement of M. baibianorum tooth plates is more similar to that of other Mesozoic and Cenozoic species (such as neoceratodontids) than it is to that present in Paleozoic species (such as Dipterus valenciennesi). At the same time, incremental lines in vertical sections are observed. The nature of incremental lines in the interdenteonal dentine and their use in estimating the minimum age of the specimen are discussed.

Optical Thouless pumping transport and nonlinear switching in a topological low-dimensional discrete nematic liquid crystal array

We theoretically investigate a Thouless pumping scheme in the 1D topological Su-Schrieffer-Heeger (SSH) model for single and multiple band-gaps systems when implemented in a discrete nematic liquid crystal arrangement. For an electrically controlled SSH waveguide array, we numerically demonstrate edge-to-edge light transport at low power levels. On the other hand, at higher powers, the transport is frustrated by light-induced nonlinear defect states, giving rise to robust all-optical switching.

Diffractive-refractive optics-possibility of long distance communication by X-rays

A novel concept is introduced to overcome the communication blackout of returning space carriers to earth from space. The concept is based on crystal optics working is a special refractive – diffractive régime. The crystal arrangement offer several advantages compared to previously introduced concepts, like light weight, stiffness and easy to align design. All these properties are very important when it comes to space born optics. Several possibilities are introduced and elaborated showing various performances of such a unique X-ray space collimator.

Synthesis, crystal growth, crystal investigation, optical, thermal, DFT and NLO studies of 2-methylanilinium- 4-methylbenzenesulfonate organic single crystal: Experimental and computational approach

1:1 Molecular adducts of 2-methylanilinium-4-methylbenzene-1-sulfonate (2MA4MBS) were synthesized and grown as a single crystal by slow evaporation elucidation procedure using aqueous medium, where 2-methylaniline acts as an acceptor and 4-methylbenzene-1-sulfonic acid acts as donor. X-ray diffraction analysis reveals that 2MA4MBS, a member of monoclinic crystal arrangement with space group P21/n. The determined unit cell dimensions are a = 12.7112(12) Å, b = 6.9448(5) Å, c = 16.1278(15) Å, β = 106.734(6)° and volume = 1363.4(2)Å3. TGA and DTA were used to evaluate the thermal properties of 2MA4MBS, which revealed excellent thermal efficiency of the produced crystals up to 180 °C. UV–Vis-NIR absorption spectra was employed to describe the crystal's absorbance in the stretch of 200–800 nm, and absorbance band maximum was determined to be at 225 nm. DFT studies has been performed on the titular compound in order to obtain stable structure, vibrational wavenumbers, there is an inter and intramolecular charge shift within the compound. Single crystal's comparative SHG reliability was determined to be 1.7 times superior to the KDP standard. With conventional KDP, the laser damage threshold for the generated crystal is 0.86 GW/cm2.