Preparation and Properties of CO2 Micro-Nanobubble Water Based on Response Surface Methodology

Carbon dioxide (CO2) enrichment in an agricultural environment has been shown to enhance the efficiency of crop photosynthesis, increasing crop yield and product quality. There is a problem of the excessive use of CO2 gas when the CO2 is enriched for crops, such as soybean and other field crops. Given the application of micro-nanobubbles (MNBs) in agricultural production, this research takes CO2 as the gas source to prepare the micro-nanobubble water by the dissolved gas release method, and the response surface methodology is used to optimize the preparation process. The results show that the optimum parameters, which are the gas–liquid ratio, generator running time, and inlet water temperature for the preparation of CO2 micro-nanobubble water, are 2.87%, 28.47 min, and 25.52 °C, respectively. The CO2 content in the MNB water prepared under the optimum parameters is 7.64 mg/L, and the pH is 4.08. Furthermore, the particle size of the bubbles is mostly 255.5 nm. With the extension of the storage time, some of the bubbles polymerize and spill out, but there is still a certain amount of nanoscale bubbles during a certain period. This research provides a new idea for using MNB technology to increase the content and lifespan of CO2 in water, which will slow the release and increase the utilization of CO2 when using CO2 enrichment in agriculture.

ZRO Drift Reduction of MEMS Gyroscopes via Internal and Packaging Stress Release

Zero-rate output (ZRO) drift induces deteriorated micro-electromechanical system (MEMS) gyroscope performances, severely limiting its practical applications. Hence, it is vital to explore an effective method toward ZRO drift reduction. In this work, we conduct an elaborate investigation on the impacts of the internal and packaging stresses on the ZRO drift at the thermal start-up stage and propose a temperature-induced stress release method to reduce the duration and magnitude of ZRO drift. Self-developed high-Q dual-mass tuning fork gyroscopes (TFGs) are adopted to study the correlations between temperature, frequency, and ZRO drift. Furthermore, a rigorous finite element simulation model is built based on the actual device and packaging structure, revealing the temperature and stresses distribution inside TFGs. Meanwhile, the relationship between temperature and stresses are deeply explored. Moreover, we introduce a temperature-induced stress release process to generate thermal stresses and reduce the temperature-related device sensitivity. By this way, the ZRO drift duration is drastically reduced from ~2000 s to ~890 s, and the drift magnitude decreases from ~0.4 °/s to ~0.23 °/s. The optimized device achieves a small bias instability (BI) of 7.903 °/h and a low angle random walk (ARW) of 0.792 °/√ h, and its long-term bias performance is significantly improved.

Formulation and Evaluation of Ficus Benghalensis Emulgel for its Anti- Rheumatoid Arthritis Effect

The current study focuses on the development and characterization of ficus benghalensis powdered aerial roots emulgel to avoid the first-pass effect and strengthen bioavailability while reducing dosage intervals and dose-related deleterious reactions. three formulations with the same concentration and different polymers were formulated. Ethanolic and petroleum ether extract of dried aerial roots of ficus benghalensis were prepared by using different gelling agents like Carbopol 934, Carbopol 940, and Xanthane gum was formulated. The prepared formulations were evaluated for their qualitative as well as quantitative tests, physical appearance, pH, viscosity, spreadability, consistency, homogeneity, moisture loss, and finally in vitro anti-arthritic activity. Depending on the outcomes, it was observed that to all the formulation, F1 formulation containing Carbopol 940 with 4.6% moisture loss, 3780.3±5.0 viscosity and 6.1±0.1 PH and 43.7±1.53 spreadability shows better activity then all the other. Herbal emulgel of ethanolic extract of dried aerial roots of ficus benghalensis line, when compared with diclofenac emulgel, confirms the anti-arthritic activity through invitro release method.

Existence and Uniqueness of Nontrivial Periodic Solutions to a Discrete Switching Model

To control the spread of mosquito-borne diseases, one goal of the World Mosquito Program’s Wolbachia release method is to replace wild vector mosquitoes with Wolbachia-infected ones, whose capability of transmitting diseases has been greatly reduced owing to the Wolbachia infection. In this paper, we propose a discrete switching model which characterizes a release strategy including an impulsive and periodic release, where Wolbachia-infected males are released with the release ratio α1 during the first N generations, and the release ratio is α2 from the (N+1)-th generation to the T-th generation. Sufficient conditions on the release ratios α1 and α2 are obtained to guarantee the existence and uniqueness of nontrivial periodic solutions to the discrete switching model. We aim to provide new methods to count the exact numbers of periodic solutions to discrete switching models.

ZRO Drift Reduction of MEMS Gyroscopes via Internal and Packaging Stress Release

Zero-rate output (ZRO) drift induces deteriorated micro-electromechanical system (MEMS) gy-roscope performances, severely limiting its practical applications. Hence, it is vital to explore an effective method toward ZRO drift reduction. In this work, we conduct an elaborate investigation on the impacts of the internal and packaging stresses on the ZRO drift at the thermal start-up stage, and propose a temperature-induced stress release method to reduce the duration and magnitude of ZRO drift. Self-developed high-Q dual mass tuning fork gyroscopes (TFGs) are adopted to study the correlations between temperature, frequency and ZRO drift. Furthermore, a rigorous finite element simulation model is built based on the actual device and packaging structure, revealing the temperature and stresses distribution inside TFGs. Meanwhile, the relationship between temperature and stresses are deeply explored. Moreover, we introduce a temperature-induced stress release process to generate thermal stresses and reduce the temperature-related device sensitivity. By this way, the ZRO drift duration is drastically reduced from ~2000 s to ~890 s, and the drift magnitude decreases from ~0.4 °/s to ~0.23 °/s. This stress release method achieves a small bias instability (BI) of 7.903 °/h and a low angle random walk (ARW) of 0.792 °/√h, and the long-term bias performance is significantly improved.

A REVIEW ON RECENT ADVANCEMENT IN PULSATILE DRUG DELIVERY SYSTEMS

Delivery systems with a pulsatile-release method are particularly involved in designing medicines for which traditional managed drug-release systems with the continuous release are not suitable. This medication also has a high first-pass impact or special conditions for chrono-pharmacology. These medications also have a high first-pass or unique chronopharmacological effect. The pulsatile release profile is characterised by a duration of no release (lag time) followed by a fast and full release of the drug. Pulsatile drug delivery systems may be classified into site-specific systems in which the drug is released inside the gastrointestinal system (e. g. colon) or time-controlled devices wherein the drug is released after a well-defined time period. Site-regulated release is typically controlled by environmental factors, such as pH or enzymes found in the intestinal tract, whereas drug release from time-controlled processes is controlled mainly by the delivery system and, preferably, not by the environment. This review covers various single-and multiple-unit oral pulsatile drug-delivery systems with an emphasis on time-controlled drug-release systems.

Review: Synthesis of Urea in Several Methods

<p>Urea (CO (NH)₂) is one of the compositions in making fertilizer. Fertilizer is crucial, especially for plant growth (affecting plant fertility). If a plant had urea fertilizer on the soil, nitrogen in the fertilizer releases quickly, and it will cause environmental pollution. Therefore, many studies want to develop urea fertilizer to be more efficient to use. The purpose of this review is to find the most appropriate method for the efficient use of urea as seen from the material used, the technique used, and the results obtained. This review shows that the most appropriate method is the slow release method with NaOH and fly ash ingredients. Because this method can increase the effective utilization of urea, reduce environmental pollution, and be relatively more straightforward, the raw material is more affordable and spread widely in the market.</p><p> </p>

Detection and quantification method intercomparison of methane emission from natural gas distribution network leaks in Hamburg, Germany

&lt;p&gt;On October 14, 2020 the European Commission adopted the EU methane strategy[1]. Measurement-based reporting of methane emissions will be crucial and may become legally binding. A variety of different methods are in use to quantify methane emissions from natural gas distribution networks, some attempting to quantify the pipeline leak under the ground, others attempting to quantify the emissions to the atmosphere. Comparisons between these methods are essential, as each method has its own advantages and limitations. In August and September 2020, we conducted an extensive campaign to compare three different methods, the mobile survey method, the tracer release method, and the suction techniques, to quantify emission rates of leaks from the natural gas distribution network in Hamburg, Germany. The mobile measurement technique employed two different cavity ringdown analyzers to identify and quantify methane, ethane and carbon dioxide using a moving vehicle. The tracer release technique measured methane and the tracer gas acetylene also with fast laser methods during driving or stationary deployment in a vehicle at an identified leak location. The suction method deployed soil sondes around an identified leak and measured methane in a stream of air pumped out of the soil until an equilibrium was reached.&amp;#160; In total, we targeted 20 locations that had been identified by mobile measurements or by the routine leak detection of the local gas utility, GasNetz Hamburg. For numerous locations we detected several emission outlets from e.g., cavities, cracks or drains and we used measurements of the ethane to methane ratio to identify possible mixture of fossil and microbial sources. We will compare the different quantification methods, including their suitability for routine application and precision and accuracy in emission quantification.&lt;/p&gt;&lt;div&gt;&lt;br&gt;&lt;div&gt; &lt;p&gt;[1] https://ec.europa.eu/energy/sites/ener/files/eu_methane_strategy.pdf&lt;/p&gt; &lt;/div&gt; &lt;/div&gt;

Plasma Hydrogen Sulfide Production Capacity is Positively Associated with Post-Operative Survival in Patients Undergoing Surgical Revascularization

ABSTRACTObjectiveHydrogen sulfide (H2S) is a gaseous signaling molecule and redox factor important for cardiovascular function. Deficiencies in its production or bioavailability are implicated in atherosclerotic disease. However, it is unknown if circulating H2S levels differ between vasculopaths and healthy individuals, and if so, whether H2S measurements can be used to predict surgical outcomes. Here, we examine: 1) Plasma H2S levels in patients undergoing vascular surgery and compare these to healthy controls, and 2) Associations between H2S levels and mortality in surgical revascularization patients.Approach & ResultsPatients undergoing carotid endarterectomy, open lower extremity revascularization or leg amputation were enrolled. Peripheral blood was also collected from a matched cohort of 20 patients without peripheral or coronary artery disease. Plasma H2S production capacity and sulfide concentration were measured using the lead acetate and monobromobimane methods, respectively. Plasma H2S production capacity and plasma sulfide concentrations were reduced in patients with PAD (p<0.001, p=0.013 respectively). Patients that underwent surgical revascularization were divided into high versus low H2S production capacity groups by median split. Patients in the low H2S production group had increased probability of mortality (p=0.003). This association was robust to correction for potentially confounding variables using Cox proportional hazard models.ConclusionsCirculating H2S levels were lower in patients with atherosclerotic disease. Patients undergoing surgical revascularization with lower H2S production capacity, but not sulfide concentrations, had increased probability of mortality within 36 months post-surgery. This work provides insight on the role H2S plays as a diagnostic and potential therapeutic for cardiovascular disease.HIGHLIGHTSVascular disease patients have higher plasma hydrogen sulfide levels than controls without vascular disease as measured by two distinct methods, the lead acetate hydrogen sulfide release method and the HPLC-based monobromobimane method.Only the lead acetate hydrogen sulfide release method robustly predicts survival after vascular surgery intervention over 35 months of follow up.The lead acetate release method measures non-enzymatic hydrogen sulfide release from plasma which requires iron and is catalyzed by vitamin B6.