Co/C Nanocomposites with Tunable Condensed States Induced by Conformation-Mediated Strategy for Electromagnetic Wave Absorption.

The strategic regulation of condensed state structures in multicomponent nanomaterials has emerged as an effective approach for achieving controllable electromagnetic (EM) properties. Herein, a novel conformation-mediated strategy is proposed to manipulate the condensed states of Co and C, as well as their interaction. The conformation of polyvinylpyrrolidone molecules is adjusted using a gradient methanol/water ratio, whereby the coordination dynamic equilibrium effectively governs the deposition of metal-organic framework precursors. This process ultimately influences the combined impact of derived Co and C in the resulting Co/C nanocomposites post-pyrolysis. The experimental results show that the condensed state structure of Co/C nanocomposites transitions from agglomerate state → to biphasic compact state → to loose packing state. Benefiting from the tunable collaboration between interfacial polarization and defects polarization, and the appropriate electrical conductivity, the diphasic compact state of Co/C nanocomposites achieves an effective absorbing bandwidth of 7.12 GHz (2.1 mm) and minimum reflection loss of -32.8 dB. This study highlights the significance of condensed state manipulation in comprehensively regulating the EM wave absorption characteristics of carbon-based magnetic metal nanocomposites, encompassing factors such as conductivity loss, magnetic loss, defect polarization, and interface polarization.

Prevalence and genetic diversity of human rhinovirus among patients with acute respiratory infections in China, 2012-2021.

To understand the prevalence of rhinovirus (RV) among acute respiratory infection (ARI) patients, 10-year ARI surveillance in multiple provinces of China were conducted during 2012-2021. Of 15 645 ARI patients, 1180 (7.54%) were confirmed to have RV infection and 820 (69.49%) were children under 5 years of age. RV typing was performed on the 527 VP1 gene sequences, and species A, B, and C accounted for 73.24%, 4.93%, and 21.82%, respectively. Although no significant difference in the proportions of age groups or disease severity was found between RV species, RV-C was more frequently detected in children under 5 years of age, RV-A was more frequently detected in elderly individuals (≥60), and the proportions of pneumonia in RV-A and RV-C patients were higher than those in RV-B patients. The epidemic peak of RV-A was earlier than that of RV-C. A total of 57 types of RV-A, 13 types of RV-B, and 35 types of RV-C were identified in RV-infected patients, and two uncertain RV types were also detected. The findings showed a few differences in epidemiological and clinical features between RV species in ARI patients, and RV-A and RV-C were more prevalent than RV-B.

Tailoring Built-In Electric Field in a Self-Assembled Zeolitic Imidazolate Framework/MXene Nanocomposites for Microwave Absorption.

Heterointerface engineering, which plays a pivotal role in developing advanced microwave-absorbing materials, is employed to design zeolitic imidazolate framework (ZIF)-MXene nanocomposites. The ZIF-MXene composites are prepared by electrostatic self-assembly of negatively charged titanium carbide MXene flakes and positively charged Co-containing ZIF nanomaterials. This approach effectively creates abundant Mott-Schottky heterointerfaces exhibiting a robust built-in electric field (BIEF) effect, as evidenced by experimental and theoretical analyses, leading to a notable attenuation of electromagnetic energy. Systematic manipulation of the BIEF-exhibiting heterointerface, achieved through topological modulation of the ZIF, proficiently alters charge separation, facilitates electron migration, and ultimately enhances polarization relaxation loss, resulting in exceptional electromagnetic wave absorption performance (reflection loss RLmin = -47.35 dB and effective absorption bandwidth fE = 6.32 GHz). The present study demonstrates an innovative model system for elucidating the interfacial polarization mechanisms and pioneers a novel approach to developing functional materials with electromagnetic characteristics through spatial charge engineering.

Comparison of the postoperative outcome with and without intraoperative leak testing for sleeve gastrectomy: a systematic review and meta-analysis of 469 588 cases.

OBJECTIVE: Postoperative staple line leakage (SLL) after sleeve gastrectomy (SG) is a rare but serious complication. Many surgeons routinely test anastomosis with an intraoperative leak test (IOLT) as part of the SG procedure. This meta-analysis aims to determine whether an IOLT plays a role in reducing the rate of postoperative staple line related complications in patients who underwent SG. METHODS: The authors searched the PubMed, Web of science, the Cochrane Library, and Clinical Trials.gov databases for clinical studies assessing the application of IOLT in SG. The primary endpoint was the development of postoperative SLL. Secondary endpoints included the postoperative bleeding, 30 days mortality rates, and 30 days readmission rates. RESULTS: Six studies totaling 469 588 patients met the inclusion criteria. Our review found that the SLL rate was 0.38% (1221/ 324 264) in the IOLT group and 0.31% (453/ 145 324) in the no intraoperative leak test (NIOLT) group. Postoperative SLL decreased in the NIOLT group compared with the IOLT group (OR=1.27; 95% CI: 1.14-1.42, P =0.000). Postoperative bleeding was fewer in the IOLT group than that in the NIOLT group (OR 0.79; 95% CI: 0.72-0.87, P =0.000). There was no significant difference between the IOLT group and the NIOLT group regarding 30 days mortality rates and 30 days readmission rates ( P >0.05). CONCLUSION: IOLT was correlated with an increase in SLL when included as a part of the SG procedure. However, IOLT was associated with a lower rate of postoperative bleeding. Thus, IOLT should be considered in SG in the situation of suspected postoperative bleeding.

Ultrasound-assisted continuous crystallization of metastable polymorphic pharmaceutical in a slug-flow tubular crystallizer.

Metastable polymorphic pharmaceuticals have garnered significant attention in recent years due to their enhanced physicochemical properties, including solubility, bioavailability, and intellectual property considerations. However, the manufacturing of metastable form pharmaceuticals remains a formidable challenge. The stable preparation of metastable carvedilol (CVD) form Ⅱ crystals during CVD production is elusive, leading to substantial inconsistencies in product quality and regulatory compliance. In this study, we successfully prepared metastable CVD Form Ⅱ crystals using a continuous tubular crystallizer. Our findings demonstrate that the tubular crystallizer exhibits high efficiency and robustness for generating metastable crystal Form Ⅱ. We optimized the crystallization process by incorporating air bubble segments and employing ultrasonic irradiation strategies to overcome blockages and wall sticking issues encountered during operation. Ultimately, we developed an ultrasound-assisted continuous slug-flow tubular crystallization method and evaluated its performance. The results indicate that the CVD crystals produced through this process are resilient, sustainable, and uninterrupted products with promising potential for producing metastable polymorphic pharmaceuticals while effectively addressing encrustation problems associated with continuous tubular crystallization.

Two Cases of Laparoscopic Resection of Siewert Type II Adenocarcinoma of the Esophagogastric Junction Using a Transhiatal Approach and Complicated by Hemopericardium.

BACKGROUND Siewert type II adenocarcinoma of the esophagogastric junction is located at the boundary of the distal esophagus and gastric cardia, and surgical resection is currently performed using open or laparoscopic methods. This report presents 2 cases of laparoscopic resection of Siewert type II adenocarcinoma of the esophagogastric junction using a transhiatal approach, complicated by hemopericardium. CASE REPORT We present 2 patients diagnosed with Siewert type II esophagogastric junction cancer. A 67-year-old man had intermittent dull pain in the epigastrium without apparent cause for 10 months. A 69-year-old man had persistent dull pain in the middle and upper abdomen for more than 3 months and acid reflux after eating. Gastroscopy with pathological examination confirmed the diagnoses. The patients underwent laparoscopic transhiatal total gastrectomy according to the Japanese Gastric Cancer Treatment Guidelines 2018 (5th edition). Pathological analysis classified the cancers as T3N1M0 and T2N0M0, respectively. The patients' cases were complicated with hemopericardium 18 h and 23 h after surgery, respectively. The shared clinical symptoms of the patients included tachycardia and low blood pressure. Cardiovascular color Doppler ultrasound and computed tomography (CT) were used to identify the hemopericardium. Following emergent ultrasound-guided pericardiocentesis and drainage, the vital signs of the patients improved. Both patients recovered well, and no other complications occurred. CONCLUSIONS Hemopericardium is a life-threatening complication for patients with esophageal-gastric junction cancer who undergo transhiatal laparoscopic surgery. Quick detection and intervention for postoperative hemopericardium following laparoscopic transhiatal total gastrectomy are important. Ultrasound-guided pericardiocentesis and drainage is effective for the treatment of postoperative hemopericardium.

Robotic versus laparoscopic surgery for hiatal hernia repair: a systematic literature review and meta-analysis.

The number of robotic hiatal hernia repairs (RHHR) is increasing. However, the superiority of this minimally invasive approach remains controversial. The aim of this study was to evaluate the available literature reporting on outcomes of RHHR compared with laparoscopic hiatal hernia repair (LHHR) in adult patients. The design of this systematic review was developed using the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Web of Science, PubMed, the Cochrane Library, and ClinicalTrials.gov databases were searched. Identified publications were reviewed independently by two authors. High heterogeneity was further explored through sensitivity analysis. The primary endpoint was the development of postoperative complications. Secondary endpoints included operation time, intraoperative complications, 30 day readmission rates and length of stay. The analysis was performed using Stata 17.0 software. A total of 7 studies totaling 10078 patients met the inclusion criteria. Five studies included postoperative complications. The postoperative complications rate was 4.25% (302/7111) in the LHHR group, and 3.49% (38/1088) in the RHHR group. Postoperative complications significantly decreased after RHHR compared with LHHR (OR 0.52; 95% CI 0.36 to 0.75, P = 0.000). Three studies involving 2176 patients reported length of hospital stay. In the three studies, the mean Length of hospital stay was 3.2 days in the RHHR group, and 4.2 days in the LHHR group. Length of hospital stay was decreased by a mean of 0.68 days for RHHR compared with LHHR (WMD, - 0.68 days; 95% CI - 1.32 to - 0.03, P = 0.02). There was no significant difference between the RHHR group and the LHHR group regarding operative time, intraoperative complications, and 30 day readmission (P > 0.05). Our research shows that RHHR may be the better option, as the approach decreases postoperative complications and length of hospital stay.

A Novel Intraoperative Leak Test Procedure (GAM Procedure) to Prevent Postoperative Anastomotic Leakage in Gastric Cancer Patients Who Underwent Gastrectomy.

BACKGROUND: Anastomotic leakage following a radical gastrectomy is a serious complication of gastric cancer and esophagogastric junction cancer. The benefit of intraoperative leak testing for the prevention of postoperative anastomotic leakage has been controversial. We introduce a new procedure, which combines the techniques of gastroscopy, air, and methylene blue (GAM) for intraoperative leakage testing. Our objective was to evaluate the efficacy and safety of the GAM procedure for intraoperative leak testing and to compare the surgical complications of gastric cancer patients who underwent gastrectomy with and without intraoperative leak testing using the GAM procedure. MATERIALS AND METHODS: A total of 210 patients who underwent radical gastrectomy for gastric cancer were included. Patients were divided into 2 groups: the intraoperative leak testing group using the GAM procedure (IOLT), and the group for which no intraoperative leak testing was done (NIOLT). Clinical and pathologic characteristics, the incidence of postoperative anastomotic leakage, and other surgical complications were compared between the 2 groups. RESULTS: There were 82 patients in the IOLT group and 82 patients in the NIOLT group after propensity score matching. In the IOLT group, 4 (4.9%) patients were found to have anastomotic discontinuity during the operation; we repaired these anastomotic discontinuities intraoperatively. The incidence of postoperative anastomotic leakage was higher in the NIOLT group compared with the IOLT group, 6 (7.3%) versus 0 (0%), respectively ( P =0.01). The average time of the GAM procedure was 4.99±1.75 minutes. The surgical time was prolonged by 30 minutes in the IOLT group compared with the NIOLT group, 302.2±79.9 versus 272.1±85.2, respectively ( P =0.02). The length of hospital stay, 15.80±4.55 versus 17.00±6.20 ( P =0.16) was reduced in the IOLT group compared with the NIOLT group. The logistic regression model suggested that IOLT, sex, age, Eastern Cooperative Oncology Group, cT stage, tumor diameter, pT stage, pN stage, and Lauren classification were not risk factors for postoperative complication. CONCLUSIONS: The GAM procedure of intraoperative leakage testing can effectively reduce the incidence of postoperative anastomotic leakage in gastric cancer patients undergoing gastrectomy.

Separation performance and agglomeration behavior analysis of solution crystallization in food engineering.

This study employed solution crystallization in food engineering to prepare a high-purity vitamin intermediate, optimize its crystal morphology and regulate its particle size distribution. Model analysis was performed to investigate the quantitative correlations between the process variables and target parameters, indicating the substantial effect of temperature on separation performance. Under optimal conditions, the product purity exceeded 99.5%, which meets the requirement of the subsequent synthesis process. A high crystallization temperature reduced the agglomeration phenomenon and increased particle liquidity. Herein, we also proposed a temperature cycling strategy and a gassing crystallization routine to optimize the particle size. The results illustrated that the synergistic control of temperature and gassing crystallization could substantially improve the separation process. Overall, based on a high separation efficiency, this study combined model analysis and process intensification pathways to explore the process parameters on product properties such as purity, crystal morphology, and particle size distribution.

Efficacy and safety of anastomotic leak testing in gastric cancer: a randomized controlled trial.

BACKGROUND: Anastomosis-related complications such as bleeding, leakage, and strictures, continue to be serious complications of gastric cancer surgery. Presently, these complications have yet to be reliably prevented. Here we design a comprehensive leak testing procedure which combines gastroscopy, air, and methylene blue (GAM) leak testing. We aimed to evaluated the efficacy and safety of the GAM procedure in patients with gastric cancer. METHODS: Patients aged 18-85 years without an unresectable factor as confirmed via CT were enrolled in a prospective randomized clinical trial at a tertiary referral teaching hospital and were randomly assigned to two groups: intraoperative leak testing group (IOLT) and no intraoperative leak testing group (NIOLT). The primary endpoint was the incidence of postoperative anastomosis-related complications in the two groups. RESULTS: 148 patients were initially randomly assigned to the IOLT group (n = 74) and to the NIOLT group (n = 74) between September 2018 and September 2022. After exclusions, 70 remained in the IOLT group and 68 in the NIOLT group. In the IOLT group, 5 patients (7.1%) were found to have anastomotic defects intraoperatively, which included anastomotic discontinuity, bleeding, and strictures. The NIOLT group had a higher incidence of postoperative anastomotic leakage compared to the IOLT group: 4 patients (5.8%) vs 0 patients (0%), respectively. No GAM-related complications were observed. CONCLUSION: The GAM procedure is an intraoperative leak test that can be performed safely and efficiently after a laparoscopic total gastrectomy. GAM anastomotic leak testing may effectively prevent technical defect-related anastomotic complications in patients with gastric cancer who undergo a gastrectomy. TRIAL REGISTRATION: Clinical Trials.gov Identifier: NCT04292496.

Effect of Substitutional Oxygen on Properties of Ti3 C2 Tx MXene Produced Using Recycled TiO2 Source.

MXenes are an emerging class of 2D materials with unique properties including metallic conductivity, mechanical flexibility, and surface tunability, which ensure their utility for diverse applications. However, the synthesis of MXenes with high crystallinity and atomic stoichiometry in a low-cost process is still challenging because of the difficulty in controlling the oxygen substitute in the precursors and final products of MXenes, which limits their academic understanding and practical applications. Here, a novel cost-effective method is reported to synthesize a highly crystalline and stoichiometric Ti3 C2 Tx MXene with minimum substitutional oxygen impurities by controlling the amount of excess carbon and time of high-energy milling in carbothermal reduction of recycled TiO2 source. The highest used content (2 wt%) of excess-carbon yields TiC with the highest carbon content and minimal oxygen substitutes, which leads to the Ti3 AlC2 MAX phase with improved crystallinity and atomic stoichiometry, and finally Ti3 C2 Tx MXene with the highest electrical conductivity (11738 S cm-1 ) and superior electromagnetic shielding effectiveness. Additionally, the effects of carbon content and substitutional oxygen on the physical properties of TiC and Ti3 AlC2 are elucidated by density-functional-theory calculations. This inexpensive TiO2 -based method of synthesizing high-quality Ti3 C2 Tx MXene can facilitate large-scale production and thus accelerate global research on MXenes.

Preparation of ethyl vanillin spherical particles with functions of sustained release and anti-caking by an organic solvent-free process.

Ethyl vanillin is an important synthetic flavor that occupies a large market share in food additives. However, the shortcomings in terms of too fast aroma release rate and poor powder properties have severely limited its further application. In this work, the intrinsic mechanism of ethyl vanillin oiling-out process is revealed with the help of process analytical technologies. Further, a green and efficient spherical particles preparation technology is developed by constructing the oiling-out phase diagram of ethyl vanillin in the aqueous solution of sodium chloride. The ethyl vanillin spherical product has excellent powder properties with high bulk density (0.74 g/cm3), good sphericity (93.4 %), high flowability (29°), high yield (>95 %) and adjustable particle size distribution. More importantly, the spherical product exhibits 57.9 % lower aroma release rate at 323.15 K and 1400 % higher critical caking cycle compared to irregularly shaped powder, which confirms its sustained release and anti-caking function.

Texture Regulation of Metal-Organic Frameworks, Microwave Absorption Mechanism-Oriented Structural Optimization and Design Perspectives.

Texture regulation of metal-organic frameworks (MOFs) is essential for controlling their electromagnetic wave (EMW) absorption properties. This review systematically summarizes the recent advancements in texture regulation strategies for MOFs, including etching and exchange of central ions, etching and exchange of ligands, chemically induced self-assembly, and MOF-on-MOF heterostructure design. Additionally, the EMW absorption mechanisms in approaches based on structure-function dependencies, including nano-micro topological engineering, defect engineering, interface engineering, and hybrid engineering, are comprehensively explored. Finally, current challenges and future research orientation are proposed. This review aims to provide new perspectives for designing MOF-derived EMW-absorption materials to achieve essential breakthroughs in mechanistic investigations in this promising field.

An Analysis of Injury Trends and Disease Burden From Three Surveillance Hospitals in Urumqi From 2006 to 2018.

Objective: To investigate injury trends, injury distribution, and disease burden from three surveillance hospitals in Urumqi from 2006 to 2018. Method: Injury data from the National Injury Surveillance System (NISS) from three hospitals in Urumqi (2006 to 2018) were collected to analyze changes in the characteristics of outpatient injury cases. Years of potential life lost (YPLL) were calculated to determine the disease burden of the injury cases. Results: A total of 161,400 injury cases were recorded over 13 years, and the average age of the patient seeking medical attention was 32.4 years old. Male patients outnumbered female patients with a ratio of 1.6:1, but the proportion of female patients was greater after 45 years of age. The highest number of cases occurred in patients 15-29 years of age, accounting for 26.8% of all injury cases. Injury in females occurred most frequently in the home. A total of 41.4% of injury cases occurred while doing housework. The top three causes of injury were falls (49.7%), blunt force of an object, (13.7%), and motor vehicle accidents (MVA) (13.5%). Years of potential life lost from injury accounted for 7.39% of the total YPLL in the three hospitals. Conclusion: Males should be targeted for injury prevention and intervention in Urumqi. The prevention of falls, blunt force of objects, and MVA should be made a priority. Injury prevention strategies and targeted projects should be developed to reduce the disease burden of injury.

Comparative analysis of the clinical and epidemiological characteristics of human influenza virus versus human respiratory syncytial virus versus human metapneumovirus infection in nine provinces of China during 2009-2021.

A comparative analysis of confirmed cases of human influenza virus (HIFV), human respiratory syncytial virus (HRSV), and human metapneumovirus (HMPV) was conducted to describe their clinical and epidemiological characteristics. During 2009-2021, active surveillance of acute respiratory infections (ARIs) was performed in nine provinces of China. Clinical and epidemiological information and laboratory testing results of HIFV, HRSV, and HMPV were analyzed. Among 11591 ARI patients, the single-infection rates of HIFV, HRSV, and HMPV were 15.00%, 9.59%, and 2.24%, respectively; the coinfection rate of these three viruses was 0.64%. HIFV infection was mainly in adults aged 15-59 years, accounting for 39.10%. HRSV and HMPV infections were mainly in children under 5 years old, accounting for 87.13% and 83.46%, respectively. Patients with HRSV infection were younger than HMPV. HRSV and HMPV had high similarities in clinical manifestations, presenting with lower respiratory symptoms. HIFV mainly presented with an upper respiratory infection. The epidemic peak of HRSV was earlier than that of HIFV, and that of HMPV was later than those of HRSV and HFIV. A total of 85.14% of coinfection cases were children under 5 years old. Coinfection might increase the risk of pneumonia in HIFV cases. During 2020-2021, the positive rates and seasonal patterns of these three viruses changed due to the impact of the COVID-19 pandemic. Certain clinical and epidemiological features were observed in HIFV, HRSV, and HMPV infections, which could be beneficial for guiding clinical diagnosis, treatment, and prevention of these three viruses in China.

Analysis and prognostic significance of tumour immune infiltrates and immune microenvironment of m6A-related lncRNAs in patients with gastric cancer.

BACKGROUND: Studies have shown that long noncoding RNAs and N6-methyladenosine play important roles in gastric cancer. The purpose of this study was to determine the correlation and prognostic value of m6A-related lncRNAs and immune infiltration in gastric cancer. METHODS: We downloaded the clinically related information and RNA-Seq transcriptome data of gastric cancer patients from the TCGA database. Univariate Cox regression analysis and Pearson analysis were used to screen out m6A-related lncRNAs. Consensus cluster analysis was used to divide the sample into two clusters, and LASSO analysis and Cox regression analysis were used to construct a risk scoring model. RESULTS: A total of 25 lncRNA expression profiles were screened, and gastric cancer patients were divided into different subtypes. Cluster 2 had a better prognosis, but its stromal score, ESTIMATE score and immune score were low. Cluster 1 was rich in resting memory CD4 T cells, regulatory T cells, monocytes, and resting mast cells, and Cluster 2 was rich in activated memory CD4 T cells and follicular helper T cells. Thirteen lncRNAs were selected to construct a risk model, and the prognosis of gastric cancer patients in the high-risk group was poor. The expression of PD-L1 in tumours is significantly higher than that in normal tissues. Univariate and multivariate Cox regression analysis results showed that the overall survival rate was significantly related to stage and the risk score, which can be used as an independent prognostic factor. The results of the heatmap and scatter plot showed that clusters (P = 0.0045) and grade (G1-2, G3, P = 0.0037) were significantly related to prognosis. The relationship between the risk score and immune cell infiltration showed that memory B cells, resting dendritic cells, M0 macrophages, and M2 macrophages were positively correlated with the risk score, while resting mast cells, monocytes, activated NK cells, and follicular helper T cells were negatively correlated with the risk score. CONCLUSION: The results of this study indicate that m6A-related lncRNAs may play an important role in the prognosis of gastric cancer patients and the tumour immune microenvironment and may provide help for the treatment of gastric cancer patients.

Core-shell Ag@C spheres derived from Ag-MOFs with tunable ligand exchanging phase inversion for electromagnetic wave absorption.

It has become greatly significant to achieve structurally tunable electromagnetic wave absorption materials (EMAs) derived from metal-organic frameworks (MOFs) via controllably continuous phase inversion. Herein, a series of core-shell Ag@C EMAs were successfully fabricated from Ag-MOFs via adjustable phase inversion. Replacing terephthalic acid (H2BDC) with 2-methylimidazole (Hmim) continuously led to the gradual transformation of Ag-MOF-5 structure into ZIF-L, which determined the crystal and morphological structure of Ag@C EMAs. In addition, due to the optimization of relaxation loss, the minimum reflection loss (RLmin) of S2 reached -50.14 dB with a thickness of 3.0 mm. The EMA derived from the original Ag-MOF had the widest absorption bandwidth (fE) of 5.44 GHz and RLmin of -47.36 dB at only 2.2 mm, respectively. This work can shed new light on the core-shell EMAs derived from phase inversion MOFs, and provide guidance to design novel high-performance EMAs.

A hollow CuS@Mn(OH)2 particle with double-shell structure for Ultra-wide band electromagnetic absorption.

Hollow materials have many advantages when acting as electromagnetic wave (EMW) absorber, such as excellent impedance matching properties, rich micro-interfaces and light weight. In this work, a novel hollow particle with double-shell composed with CuS and Mn(OH)2 is synthesized by coordination etching, precipitation and sulfuration using tetrakaidecahedral Cu2O as template. These hollow particles are expected to be used as improved EMW absorption property at an ultra-wide band. In this hollow particle, tetrakaidecaheral CuS acts as inner shell and Mn(OH)2 acted as outer shell, thus having rich heterogeneous interfaces which induce strong interfacial polarization. Moreover, the lower electrical conductivity and loose structure of the Mn(OH)2 shell facilitates the entry of EMW into the absorbers, and the hollow structure in this particle is beneficial to improve the impedance matching according to Maxwell-Garnett (MG) theory. Therefore, hollow CuS@Mn(OH)2 particles with double-shell exhibit excellent EMW absorption performance. The effective absorption bandwidth (reflection loss (RL) ≤ -10 dB) is 6.88 GHz (from 11.12 GHz to 18 GHz) at 2.3 mm thickness of sample.

Enhancing continuous reactive crystallization of lithium carbonate in multistage mixed suspension mixed product removal crystallizers with pulsed ultrasound.

In this work, pulsed ultrasound was used to facilitate steady-state reactive crystallization and increase the final yield and productivity of lithium carbonate in continuously operated single and multistage mixed suspension mixed product removal (MSMPR) crystallizers. Experimental analyses of the stirred tank MSMPR cascade were performed to investigate the effects of ultrasound field, residence time and temperature which contributed to the steady-state yield, crystal size distribution and crystal morphology. The results show that pulsed ultrasound can not only significantly enhance the reaction rate, but also help to improve the particle size distribution and the crystal habit. Subsequently, a population balance model was developed and applied to estimate the final yield of the continuous process of the lithium bicarbonate thermal decomposition reaction coupling lithium carbonate crystallization. The consistency of the final yield between the experiments and the simulations proved the reliability of the established model. Through the experimental and simulation analyses, it is demonstrated that the use of pulsed ultrasound, higher final stage temperature, MSMPR cascade design and appropriate residence time help to achieve higher yield and productivity. Furtherly, based on the conclusion drawn, pulsed ultrasound enhanced three-stage MSMPR cascaded lithium carbonate continuous crystallization processes were designed, and the maximum productivity of 44.0 g/h was obtained experimentally.

Ultrasound-assisted solution crystallization of fotagliptin benzoate: Process intensification and crystal product optimization.

The ultrasound-assisted crystallization process has promising potentials for improving process efficiency and modifying crystalline product properties. In this work, the crystallization process of fotagliptin benzoate methanol solvate (FBMS) was investigated to improve powder properties and downstream desolvation/drying performance. The direct cooling/antisolvent crystallization process was conducted and then optimized with the assistance of ultrasonic irradiation and seeding strategy. Direct cooling/antisolvent crystallization and seeding crystallization processes resulted in needle-like crystals which are undesirable for downstream processing. In contrast, the ultrasound-assisted crystallization process produced rod-like crystals and reduced the crystal size to facilitate the desolvation of FBMS. The metastable zone width (MSZW), induction time, crystal size, morphology, and process yield were studied comprehensively. The results showed that both the seeding and ultrasound-assisted crystallization process (without seeds) can improve the process yield and the ultrasound could effectively reduce the crystal size, narrow the MSZW, and shorten the induction time. Through comparing the drying dynamics of the FBMS, the small rod-shaped crystals with a mean size of 9.6 µm produced by ultrasonic irradiation can be completely desolvated within 20 h, while the desolvation time of long needle crystals with an average size of about 157 µm obtained by direct cooling/antisolvent crystallization and seeding crystallization processes is more than 80 h. Thus the crystal size and morphology were found to be the key factors affecting the desolvation kinetics and the smaller size produced by using ultrasound can benefit the intensification of the drying process. Overall, the ultrasound-assisted crystallization showed a full improvement including crystal properties and process efficiency during the preparation of fotagliptin benzoate desolvated crystals.