Acid Crystals Research Articles

The Effect of Layer Leaves on Reducing Uric Acid in the Elderly: A Systematic Review

Gout is an inflammatory disease of the joints caused by excess uric acid content in the blood, resulting in a buildup of uric acid crystals in the joints and other soft tissues. Bay leaf or with the Latin name Syzygium Polyanthum is a plant that can be used to treat gout. This study aims to estimate the effect of bay leaves on reducing uric acid levels in the elderly. This research is a systematic review research using the PRISMA diagram. Article searches were carried out based on the PICO Model eligibility criteria. P= Elderly; I= Drink boiled bay leaves; C= Do not drink bay leaf decoction; O= Uric acid. The articles used come from 1 database, namely: Google Scholar. With keywords including "gout" AND "bay leaf" AND "elderly" In 5 articles from 2016-2022, it can be concluded that regarding the effect of bay leaves on gout in the elderly, it shows that boiling bay leaf water can reduce uric acid in the elderly.

The high‐pressure response of trans‐cinnamic acid crystals studied by Raman spectroscopy

AbstractThe pressure response of crystalline trans‐cinnamic acid is studied by means of Raman spectroscopy up to 6 GPa. Pressure application causes the reversible shift of all the observed Raman peaks to higher frequencies and changes in their relative intensities, with the intermolecular vibrational modes being by far more sensitive to pressurization compared to the intramolecular ones. The present high‐pressure Raman data indicate the structural stability of the trans‐cinnamic acid crystal and molecular conformation up to the highest pressure attained in the experiments, the importance of the hydrogen bonding, as well as the considerable strengthening of the intermolecular interactions at elevated pressures.

Growth, characterization, and anti-bacterial activity of l-methionine supplemented with sulphamic acid single crystals

Abstract Sulphamic acid (SA) crystals supplemented with l-methionine (LM) were grown at moderate temperatures using a slow evaporation procedure. The powder XRD pattern showed that LM supplemented with SA (LMSA) crystals have an orthorhombic crystal structure. The FTIR studies confirmed the presence of various vibrational modes. Using a UV-Vis spectrometer, the transmittance of LMSA in the UV and visible range was observed, and the band gap of the LMSA was also calculated. The hardness value of LMSA was higher compared to that of pure SA. Photoluminescence emission studies of LMSA pointed out emissions at 491 and 542 nm, which were attributed to the transition from the 5D4 state to 7F6 and 7F5 ground, respectively. LMSA crystals were effective in killing pathogenic bacteria, according to the studies on their anti-bacterial activity.

EDUKASI PEMANFAATAN TANAMAN HERBAL DALAM MENGOBATI PENYAKIT YANG SERING TERJADI DI MASYARAKAT

Abstract Hypertension, cholesterol, gout and ARI are diseases that often infect the community. High blood pressure is what causes hypertension. This increases the chance of heart disease and stroke as well as other health problems. The body makes cholesterol from fats found in animal products. Due to the presence of uric acid crystals, gout conditions cause joint pain or inflammation. Infections that attack the respiratory tract and are caused by viruses are called acute respiratory infections or ARI. The service technique is carried out through lectures and discussions about diseases that often attack the surrounding environment and the use of medicinal plants in nature. It is hoped that the public will become more familiar with various diseases, including hypertension, cholesterol, gout and ARI, use herbal plants to cure these diseases, and become more concerned about their own health as a result of service activities. Kata Kunci: Hypertension, Cholesterol, Uric Acid, ARI

Investigation of encapsulated water wire within self-assembled hydrophilic nanochannels, in a modified γ4-amino acid crystals: Tracking thermally induced changes of intermolecular interactions within a crystalline hydrate

Nanostructures formed by the self-assembly of modified/unmodified amino acids have the potential to be useful in several biological/nonbiological applications. In that regard, the greater conformational space provided by γ-amino acids, owing to their additional backbone torsional degrees of freedom and enhanced proteolytic stability, compared to their α-counterparts, should be explored. Though, modified single amino acid-based nanomaterials such as nanobelts or hydrogels are developed by utilizing the monosubstituted γ-amino acids derived from the backbone homologation of phenylalanine (Phe). Examples of a single γ-amino acid-based porous nanostructure capable of accommodating solvent molecules are not really known. The crystal structures of a modified γ4(R)Phe residue, Boc-γ4(R)Phe-OH, at different temperatures, showed that hydrogen-bonded water molecules are forming a wire inside hydrophilic nanochannels. The dynamics of intermolecular interactions between the water wire and the inner wall of the channel with relation to the temperature change was investigated by analyzing the natural bonding orbital (NBO) calculation results performed with the single crystal structures obtained at different temperature points. The NBO results showed that from 325 K onward, the strength of water–water interactions in the water wire are getting weaker, whereas, for the water–inner wall interactions, it getting stronger, suggesting a favorable change in the orientation of water molecules with temperatures, for the latter.

Effect of New Low-cost Polyglutamic Acid fertilizer on Cucumber Growth

Polyglutamic acid produced from the mother liquor of glutamic acid crystals was used as a test fertiliser to study its application in cucumber cultivation. The results showed that the application of polyglutamic acid fertiliser could increase cucumber plant height, plant pitch, number of leaves, root dry matter weight, promote cucumber growth, increase cucumber single melon weight and total yield, and at the same time, it could increase the content of Vc and soluble sugar in cucumber fruits and improve the quality of cucumber. Among them, the application of polyglutamic acid fertiliser increased the plant height of cucumber by 6.3%-39.5% during the flowering period, increased the plant height by 1.8%-12.1% during the melon blooming period, increased the root dry matter weight by 92.8%, increased the weight of single melon by 4.01%-37.12%, and increased the total output by 1.31%-12.87%; the application of two polyglutamic acid fertilisers increased the vitamin C of cucumber fruits by 14.36 % and 28.12 %, and the soluble sugar content by 16.91 % and 35.29 %.

Preparation of ultra-sensitive and highly specific miniature hydrogen sensors by <i>in situ</i> synthesis methods

Hydrogen, as one of the most well-developed green energy materials, has played an important role in industrial development, human production and life, and the treatment of diseases in recent years. Hydrogen sensor is an important safety monitoring equipment in chemical production. Developing long-term and efficient hydrogen gas sensor for real-time monitoring has become increasingly important and urgent. Hydrogen, as one of the main combustible gases present in the petrochemical production process, is of great research significance and challenging in meeting the need of cycling gas identification and highly sensitive detection. Therefore, it is of great practical value to develop the low-cost, low-power and highly sensitive miniature hydrogen gas sensors . In this work, a gold-doped tin dioxide nanostructured ultra-sensitive and highly specific micro-nanosensor is obtained based on the in-situ synthesis of micro-hot plates. It is shown that the sensitivity of this nanosensor is as high as 100 for hydrogen at 50 ppm, and the sensitivity of ethanol, an important interference gas, is only 1/22 of that of hydrogen at the same concentration, which has an obvious suppression effect. For the same concentration of carbon monoxide, methane and other interference gases do not show any response. XPS characterization shows that the defective oxygen ratio of the material is the main reason for the ultra-sensitivity of the sensor. Meanwhile, in this study, the precursor solution of gold-doped tin dioxide is prepared by using chloroauric acid and tin tetrachloride crystals as raw materials; the nanosized morphology structure is prepared by templating the generation of sensitive materials using polystyrene microspheres; the in-situ synthesis method is realized by applying a voltage to the calcination of a micro hot plate. Through this nanoscale templating in-situ heating method, a gold-loaded tin dioxide nanosensor is prepared. Note that the template assisted in-situ grown <inline-formula><tex-math id="M5">\begin{document}$ {\mathrm{A}}{\mathrm{u}} $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20231265_M5.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20231265_M5.png"/></alternatives></inline-formula> loaded Tin Oxide nano sensor is abbreviated as <inline-formula><tex-math id="M6">\begin{document}$ {\mathrm{T}}{\mathrm{I}}{\mathrm{S}}\text{-}{\mathrm{Au}}\text{-}{{\mathrm{S}}{\mathrm{n}}{\mathrm{O}}}_{2} $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20231265_M6.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20231265_M6.png"/></alternatives></inline-formula> Sensor . In order to illustrate the sensing mechanism, we analyze the elemental compositions, and the results show that under the condition of the high defective oxygen content, the in-situ heating method of templated preparation of <inline-formula><tex-math id="M7">\begin{document}$ {\mathrm{A}}{\mathrm{u}}\text{-}{{\mathrm{S}}{\mathrm{n}}{\mathrm{O}}}_{2} $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20231265_M7.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20231265_M7.png"/></alternatives></inline-formula> nano-sensor containing arrays of polystyrene spheres becomes an important reason for the ultra-sensitivity to hydrogen, high specificity, and the suppression of the important interfering gas, ethanol. Moreover, the in situ preparation method can be flexibly and scalably used to prepare high-performance miniaturized gas sensors with a variety of hollow-sphere nanostructured metal oxides, in order to obtain excellent sensitivity and adjustable selectivity.

Resistive pulse analysis of chiral amino acids utilizing metal-amino acid crystallization differences.

Here, we report a proof-of-concept resistive pulse method for analyzing chiral amino acids utilizing metal-amino acid crystallization differences. This method involves introducing an amino acid sample solution into a micropipette through a pressure-driven flow. The sample then mixes with a metal ion solution inside the pipette, forming metal-amino acid crystals. The crystal size depends on the enantiomeric excess (x) of chiral amino acid samples. Large x values lead to large crystals. The crystal size difference is then reflected in the resistive pulse size as they block the ionic transport in a micropipette to different extents. We used Cd-cystine crystallization as a model system and found approximately five times the mean current pulse size difference for racemic (x = 0) and L-only (x = +1) cystine samples. A similar result was observed for aspartate. Our discovery opens up new opportunities for micro/nanoscopic chiral amino acid analysis, which can potentially be used in single-cell analysis.

A Retrospective Cross-sectional Analysis of Renal Complications in Association with Cancer: Insights from 120 Autopsies

Introduction: Kidney diseases frequently complicate cancer and its treatment, contributing to both morbidity and mortality. Malignancies can give rise to various kidney issues, such as glomerulonephritis and Chronic Kidney Disease (CKD). This association operates bidirectionally, with patients experiencing the development of renal diseases due to cancer, and CKD predisposing to cancer. Furthermore, nephrotoxicity induced by chemotherapy can result in Acute Tubular Injury (ATI) and necrosis, imposing limitations on its application. Aim: To evaluate the spectrum of renal pathology in autopsies of malignancies. Materials and Methods: This was a retrospective crosssectional study of complete autopsies of all cases of malignancies performed in the Department of Pathology, Seth GS Medical College and KEM Hospital, Mumbai, Maharashtra, India. The study was carried out over a 5-year period from January 2015 to December 2019. Analysis of cases with respect to demographics, type of primary malignancy, gross and microscopic features, and the final cause of death was conducted. These findings were meticulously tabulated, with frequencies and percentages calculated for each category. Results: A total of 4392 autopsies were conducted throughout the study period, with 120 of them revealing the presence of malignancies. A total of 38 (31.6%) malignancies were diagnosed for the first time at autopsy. The commonest renal findings on gross were scars (superficial and deep) seen in 40 (33.33%), followed by cortical cysts in 25 (20.83%), granular contracted kidney in 15 (12.50%), mass lesions in 7 (5.83%), abscesses in 7 (5.83%), and swollen, oedematous kidneys in 6 (5%) autopsies. The most frequent renal pathology on microscopy were infective lesions seen in 43 (35.83%), Acute Tubular Necrosis (ATN) in 32 (26.66%), ATI in 30 (25%), followed by malignancies- primary and secondary in 11 (9.16%), tubular casts in 6 (5%), etc. Rare findings included membranous glomerulonephritis and Tumour Lysis Syndrome (TLS) (Acute urate nephropathy) in 1 (0.83%) each. The TLS case had classic histomorphological features of TLS, apart from laboratory parameters. Extensive deposits of uric acid crystals were seen obstructing the tubules as well as some of the glomeruli on microscopy. Conclusion: In one-third of the cases, the malignancy was exclusively discovered during the autopsy. The study revealed a diverse array of lesions, encompassing pyelonephritis, ATN, primary and metastatic renal tumours, cast nephropathy, membranous glomerulonephritis, and TLS. One-fifth of the cases had end-stage renal disease (advanced renal disease). A significant number of the cases exhibited tumour masses within the kidneys. One-fifth of the cases had renal pathology contributing to the final cause of death, further highlighting the association between malignancies and renal pathology

Computed tomography-current status and future directions for arthritis imaging.

Applications of computed tomography (CT) in arthritis imaging have rapidly expanded in recent years due to ongoing technical developments. Dual-energy CT (DECT) has become indispensable in clinical practice, particularly for diagnosing gouty arthritis and assessing bony structural changes. Technological innovations such as low-dose CT and state-of-the-art reconstruction algorithms reduce radiation exposure while maintaining image quality and short acquisition times. This review explores the growing role of CT in arthritis imaging. Recent innovations have extended DECT's utility beyond gout diagnosis to the detection of inflammatory changes in various arthritic conditions. Postprocessing techniques such as the generation of subtraction images and iodine maps provide valuable insights into tissue perfusion and inflammatory activity, crucial for arthritis management. DECT can distinguish calcium from uric acid crystals, facilitating the differential diagnosis of various crystal arthropathies in a variety of clinical settings. This ability is particularly valuable in distinguishing between different clinical conditions in patients with inflammatory joint changes within a single imaging examination. Moreover, the advent of four-dimensional CT promises a better assessment of dynamic joint instabilities and ligament injuries, especially in the wrist. Overall, DECT offers a comprehensive approach to arthritis imaging, from the detection of structural changes to the assessment of active inflammation in joints and tendons. Continuous advances in CT technology, including photon-counting CT, hold promise for further improving diagnostic accuracy and expanding the role of CT in arthritis imaging and therapy monitoring.

A ultra‐low viscosity stearic acid emulsion prepared by lauric acid as waterproof agent for cement mortar

AbstractSafe building structures cannot be achieved without reliable waterproofing engineering. To address the susceptibility of concrete materials to water leakage, a low‐viscosity stearic acid emulsion has been developed as a waterproofing agent for mortar. By introducing lauric acid, the formation of stearic acid crystals in water could be effectively prevented, resulting in a stearic acid emulsion with a viscosity of only 24 mPa·s. It is found that the best overall performance was achieved when the ratio (R) of lauric acid to stearic acid was 2/3. This emulsion has the least effect on mortar fluidity and setting time. The as‐prepared modified mortar possessed the highest compressive strength (127% of the blank) and the lowest water absorption at 48 h (37% of the blank). X‐ray diffraction (XRD), Fourier‐transform infrared spectroscopy (FTIR), energy‐dispersive x‐ray spectroscopy (EDS), scanning electron microscopy (SEM), dynamic light scattering (DLS) particle size analysis, and water contact angle measurements were used to investigate the mechanism of stearic acid emulsion's modification. It is determined that the stearic acid emulsions successfully modified the internal and external hydrophobicity of the mortar by chemical action with calcium hydroxide.

A sustainable method for lithium recovery from waste liquids: Thermodynamic analysis and application

In this study, lithium was efficiently enriched and recovered from low concentration waste liquids by sodium phosphate precipitation and wet conversion. Firstly, the efficient extraction of lithium at low concentration was realized based on the lower solubility of lithium phosphate. The factors involved in the lithium phosphate precipitation process by sodium phosphate were systematically investigated, and it was discovered that the high temperature process promoted the formation of lithium phosphate, with the lithium precipitation rate reached 94.32% under optimal conditions. The feasibility of the conversion of lithium phosphate into lithium chloride solution and iron phosphate by ferric chloride solution was analyzed by thermodynamic study. The experimental results also further confirmed that the lithium conversion rate was as high as 96.06% when the reaction temperature was 25 °C and the pH of the system was 2. The conversion process achieved the enrichment of lithium from low to high concentrations, avoiding the high energy consumption caused by conventional evaporation and concentration. More importantly, the alkaline leaching of the converted residue realized the separation of phosphorus and iron sources, and then the re-synthesis of ferric chloride solution and sodium phosphate reagent was accomplished by acid leaching and crystallization, respectively, allowing for reagent recycling in the lithium extraction process. The proposed process is expected to provide a green and sustainable route for the recovery of low concentration lithium from waste liquids.

Recovery of Bio-Based Fumaric Acid By Electrochemically Induced pH Shift Crystallization

The heterotrophic microbial production of platform chemicals is gaining increasing interest due to the growing need to replace fossil resources by renewable alternatives. Carboxylic acids such as fumaric acid are important building blocks for high-value bio-based chemicals [1]. Fumaric acid is used as an acidulant, as an antibacterial agent, and as a precursor for polymers and pharmaceuticals [2,3].A major challenge commercializing the microbial production route is the recovery and the purification of fumaric acid after fermentation. Bio-production of fumaric acid has not yet reached industrial scale due to high additive consumption during the acid- and base-induced pH shift in the downstream process. The inevitable co-production of saline waste deteriorates process economics further and raises ecological concerns.Therefore, we propose a new electrochemical downstream process, which reduces the use of pH adjustment agents [4]. This downstream process incorporates an electrolysis cell to adjust the pH value. During electrolysis, protons are produced at the anode and hydroxide ions are produced at the cathode by the electrochemical splitting of water. In conventional water electrolysis, protons or hydroxide ions migrate through a membrane to balance the charge in the electrolysis cell. Consequently, the pH value is constant in the electrolysis cell chambers. In pH shift electrolysis, a salt is added to the electrolyte. The salt provides additional ions to maintain electroneutrality in both electrolysis cell chambers. In this way, protons and hydroxide ions are retained in their respective chambers of the electrolysis cell and a pH difference is created between the anode and cathode. During acidification in the anode chamber, the fumaric acid salt from the fermentation is protonated. Subsequently, fumaric acid crystallizes in the electrolysis cell in high yields due to its low solubility. Afterwards, fumaric acid crystals can be easily separated from fermentation broth. Simultaneously, a base is produced at the cathode, which can be used to maintain a neutral pH in the fermentation. Consequently, saline waste production and its drawbacks are avoided.This work presents the pH shift with an electrolysis cell and the simultaneous crystallization of fumaric acid in the anode chamber. Next, the process is analyzed using on-line and off-line analytics such as Raman spectroscopy and high-performance liquid chromatography.[1] Bozell, J. J., & Petersen, G. R. (2010). Technology development for the production of biobased products from biorefinery carbohydrates - The US Department of Energy’s “Top 10” revisited. Green Chem, 12(4), 525-728. DOI: 10.1039/B922014C[2] Xu, Q., Li, S., Huang, H., & Wen, J. (2012). Key technologies for the industrial production of fumaric acid by fermentation. Biotechnol Adv, 30(6), 1685-1696. DOI: 10.1016/j.biotechadv.2012.08.007[3] Roa Engel, C. A., Straathof, A. J., Zijlmans, T. W., van Gulik, W. M., & van der Wielen, L. A. (2008). Fumaric acid production by fermentation. Appl Microbiol Biotechnol, 78, 379-389. DOI: 10.1007/s00253-007-1341-x[4] Kocks, C., Wall, D., & Jupke, A. (2022). Evaluation of a Prototype for Electrochemical pH-Shift Crystallization of Succinic Acid. Materials, 15(23), 8412. DOI: 10.3390/ma15238412

Adsorption Isotherms of Enantiomer on Hippuric Acid Crystals Obtained under Viedma Ripening Conditions Using a Temperature Gradient

Adsorption Isotherms of Enantiomer on Hippuric Acid Crystals Obtained under Viedma Ripening Conditions Using a Temperature Gradient

Description Of Increased Uric Acid Levels In Ujung Tanduk Village Communities Before And After Drinking Tuak

Tuak is a type of alcoholic drink made from palm sugar. Continuous excessive consumption of palm wine can increase uric acid levels in the body. Uric acid is part of purine metabolism, but if metabolism occurs abnormally there will be a process of accumulation of uric acid crystals in the joints which causes quite high levels of pain such as joint disorders (Gouty arthritis). The aim is to determine the description of uric acid levels before and after consuming palm wine in residents in Ujung Tanduk Village, Laguboti District. The research that will be used is a quantitative type of research with a descriptive research design, with a purposive sampling technique. The results showed that 8 research samples, 2 people (25%) of the sample consuming 4 glasses of palm wine experienced a decrease in uric acid levels with an average of 0.25 mg/dl, 4 people (50%) of the sample consuming 6 glasses of palm wine experienced an increase in uric acid levels with an average of 0.4 mg/dl, and 2 people (25%) of the sample who consumed 8 glasses of palm wine experienced an increase in uric acid levels with an average of 1.25 mg/dl. Consuming too much palm wine can increase uric acid, therefore reducing the frequency of consuming palm wine can reduce uric acid levels.

Recovery of tungsten from spent selective catalytic reduction catalyst by sulfuric acid precipitation and evaporation crystallization method

AbstractBACKGROUNDSelective catalytic reduction (SCR) can effectively handle NOx from flue gas in coal‐fired power plants. However, as the core part of the SCR method, V2O5–WO3/TiO2 catalyst has a limited operational life in the complex flue gas environment. The recovery of rare metals from spent catalyst would not only bring economic benefits but also solve environmental problems. The process of reducing acid leaching and further roasting‐water leaching could realize the efficient recycling of vanadium, tungsten and titanium.RESULTSAfter reducing acid leaching and roasting‐water leaching to treat spent SCR catalyst, the obtained solution containing tungsten was used as the raw material in this study. The optimal pH value of solution for removal of silicon and aluminum impurities was 9.2–9.5. The best tungsten precipitation conditions were shown as follows: a tungsten concentration of 30 g L−1, a sulfuric acid concentration of 8 mol L−1, reaction temperature of 70 °C and reaction time of 2 h. Under the optimal tungsten precipitation conditions, the tungsten precipitation efficiency can reach 92.53%. Finally, in order to further improve the purity of the crude H2WO4, the crude H2WO4 was fully dissolved in ammonia, followed by filtration and evaporation crystallization to obtain 5(NH4)2O.12WO3.5H2O (APT) crystals with a purity of 93.05 wt%. The crystallization efficiency of APT was 73.37% at 60 °C for 2 h with a rotor speed of 400 rpm.CONCLUSIONThese results indicated that a higher purity of APT crystals can be obtained by the steps of removing silicon and aluminum, precipitation of tungsten by sulfuric acid, ammonia dissolution and evaporation crystallization. © 2023 Society of Chemical Industry (SCI).

Thermal effects connected to crystallization dynamics: A lattice Boltzmann study

The possible impact of temperature differences during crystal growth is investigated in this study. The organic molecule considered is mandelic acid, an important component for the pharmaceutical industry. The productivity of generating pure mandelic acid crystals are largely determined by the growth process. Reaction conditions, purity of the components, supersaturation, temperature, but possibly also temperature gradients play a central role during crystal growth. In this study a numerical model based on a hybrid solver combining the lattice Boltzmann method with finite differences is developed to model the crystallization dynamics of (S)-mandelic acid (S-ma) taking quantitatively into account temperature effects. At first, the fourth-order finite-difference method used to model energy and species conservation is validated. Then, comparisons are carried out regarding temperature changes within the single-crystal growth cell. In practice, the molar heat generation at the crystal interface shows only a small effect on the temperature field in the surrounding domain, with temperature differences below 1.5 degree. Finally, the study is extended to investigate the impact of forced convection on the crystal habits while taking into account temperature differences.

An effective method for the direct crystallization of xylonic acid from fermentation broth of agricultural residue hydrolysate

Xylose is the second most abundant sugar in nature and conversion of xylose to xylonic acid (XA) has become a research hotspot in recent years. Xylonic acid can be applied in the equivalent market niche of gluconic acid, due to their similar physical properties. XA bioproduction and application presents certainly a promising approach for xylose valorization in lignocellulose biorefinery, while the XA crystallization is so far still an unattainable goal. In this paper, an original method was proposed and experimentally investigated for the first time to get XA crystals from fermentation broth. In the XA crystallization, methanol was introduced as buffer-cum-solvent. The H2SO4 was dropwise added into the methanol solution dissolving potassium xylonate that is beforehand produced by fermentation. During H2SO4 blending with methanol, the strong and polar H2SO4 leads to XA diffusion and aggregation. Overall, 2.21 g of xylonic acid crystals was obtained per gram of 98% H2SO4 acidification. NMR detection showed that over 99% purity of XA crystals was finally obtained at the yields of 67.2% from xylonate. The integrated process could provide a practicable and effective technology for the high-qualify XA preparation from xylose derivations and lignocellulose biomass biorefinery.

Effect of ambient gas and crystal features on Doppler ultrasound twinkling of pathological mineralizations.

Color Doppler twinkling on kidney stones and other pathological mineralizations is theorized to arise from stable microbubbles, which suggests twinkling will be sensitive to ambient gas. Here, lab-grown cholesterol, calcium phosphate, and uric acid crystals were imaged with ultrasound in water while varying oxygen, carbon dioxide, and nitrogen levels. Twinkling was found to increase on cholesterol in elevated oxygen, cholesterol and calcium phosphate in elevated carbon dioxide, and no crystals in elevated nitrogen. These results support the crevice microbubble theory of twinkling and suggest gases may be varied to enhance twinkling on some mineralizations.

Adsorption Isotherms of Enantiomer on Hippuric Acid Crystals Obtained under Viedma Ripening Conditions Using a Temperature Gradient

The work is devoted to the study of the capacity for chiral recognition during the adsorption process of hippuric acid crystals obtained by the temperature gradient method under Viedma ripening conditions. This method is distinguished by the fact that the primary violation of chiral equilibrium between the nuclei formed during crystallization is not caused by the mechanical action of the stirrer but by crystallization at low temperatures. Limonenes and α-pinenes were used as test enantiomers. Adsorption isotherms were obtained using inverse gas chromatography, and their analysis made it possible to establish the chiral recognition ability of the surface. It was shown that both the enantioselectivity and adsorption capability of the synthesized hippuric acid crystals were significantly higher than those of crystals obtained under classical Viedma ripening conditions. High surface heterogeneity is probably the reason for this phenomenon.