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This work analysed the principle of flocculation purification method and the flocculation purification effect of fully synthesized water-based cutting fluid under experimental conditions, and the anti-corrosion performance of the purified cutting fluid was studied. Then, the engineering application of flocculation purification method in the centralized liquid supply system was carried out to form a flocculation purification method suitable for the Centralized liquid supply and chip removal system of fully synthesized water-based cutting fluid. This work can provide an effective evolutionary method for the fully synthetic water-based chip cutting fluid of the centralized liquid supply system.

Acetone is a biomarker found in the expired air of patients suffering from diabetes. Therefore, early and accurate detection of its concentration in the breath of such patients is extremely important. We prepared Tin(IV) oxide (SnO2) nanospheres via hydrothermal treatment and then decorated them with bimetallic PtAu nanoparticles (NPs) employing the approach of in situ reduction. The topology, elemental composition, as well as crystal structure of the prepared materials were studied via field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. The findings revealed that bimetallic PtAu-decorated SnO2 nanospheres (PtAu/SnO2) were effectively synthesized as well as PtAu NPs evenly deposited onto the surface of the SnO2 nanospheres. Pure SnO2 nanospheres and PtAu/SnO2 sensors were prepared, and their acetone gas sensitivity was explored. The findings demonstrated that in comparison to pristine SnO2 nanosphere sensors, the sensors based on PtAu/SnO2 displayed superior sensitivity to acetone of 0.166–100 ppm at 300 °C, providing a low theoretical limit of detection equal to 158 ppm. Moreover, the PtAu/SnO2 sensors showed excellent gas response (Ra/Rg = 492.3 to 100 ppm), along with fast response and recovery (14 s/13 s to 10 ppm), good linearity of correlation, excellent repeatability, long-term stability, and satisfactory selectivity at 300 °C. This improved gas sensitivity was because of the electron sensitization of the Pt NPs, the chemical sensitization of the Au NPs, as well as the synergistic effects of bimetallic PtAu. The PtAu/SnO2 sensors have considerable potential for the early diagnosis and screening of diabetes. [ABSTRACT FROM AUTHOR]

The act of standing up is one of the most important movements in daily life, but it often poses challenges for elderly individuals with declining physical functions. To address this issue, we have designed an assistive device for sit-to-stand (STS) movement. This device aids the upper limbs, allowing them to bear some of the weight during the STS movement, thereby improving the force distribution on the lower limbs and enhancing the stability of the body during movement. The connection to the user is very straightforward; one simply needs to place their hands and arms on the lifting mechanism to connect, and after the STS movement is completed, the user can easily disengage, making it very convenient to use. The device is compact, equipped with wheels and a handle, allowing it to be flexibly moved and used in confined spaces such as bedrooms, bathrooms, and balconies. ADAMS-LifeMOD simulations indicate that the use of the STS movement assistive device can significantly improve the force distribution across the joints of the lower limbs and reduce the pressure on the soles of the feet against the ground. Subsequently, a prototype was built, and four volunteers were invited to conduct further experimental validation, comparing the changes in plantar pressure during the STS movement with and without the assistive device, as well as the subjective feelings of the users. The experimental results demonstrate that the device can effectively help users to stand up more easily. [ABSTRACT FROM AUTHOR]

Image sensors on silicon have the problems of small size and high cost. Therefore, we propose a method for making image sensors on glass substrates and analyzes the feasibility of replacing Image Sensors on Silicon from the performance and cost. Through calculation and measurement, the scanning resolution, conversion gain, signal‐to‐noise ratio, and scanning time of image sensors on glass substrates can all meet the requirements of the document scanner and barcode scanner; In addition, the image sensors on glass can be formed in large size and does not require splicing, resulting in lower costs compared to image sensors on silicon of the document scanner. Therefore, image sensors on glass can replace image sensors on silicon of the document scanner. The cost and the module size of the barcode scanner is higher than the existing product, So image sensors on glass used for barcode scanners is lack of advantages in application. [ABSTRACT FROM AUTHOR]

Gaseous SO2 acidification Ce-based catalysts were prepared and used for the selective reduction of NO with NH3. S–Ce was obtained by direct anaerobic sulfation of CeO2, while H–S–Ce was obtained by reduction of CeO2 and then anaerobic sulfation. Both S–Ce and H–S–Ce exhibited excellent SCR activity, and the S–Ce catalyst displayed the best catalytic performance. The activity of CeO2 was below 30% in the whole temperature range, while the activity of S–Ce reached 90% at 250 °C and remained 100% at 300–450 °C. Anaerobic sulfation could enhance the redox and surface acidity of the S–Ce catalyst. The acid sites favored NH3 adsorption, while the H–S–Ce catalyst exhibited considerable surface acidity, but the redox performance was weakened by stable sulfate. The reaction mechanism showed that a huge number of NH3 species adsorbed on S–Ce catalysts were consumed by NO gas. The present nitrate species and NO2 were removed. The SCR reaction followed E–R and L–H mechanisms for S–Ce. A large number of NH3 species on H–S–Ce were cleared by NO, and NO could hardly adsorb on its surface. The SCR reaction followed the E–R mechanism. [ABSTRACT FROM AUTHOR]

Graphene quantum dots (GQDs), as 0D graphene nanomaterials, have aroused increasing interest in chemiresistive gas sensors owing to their remarkable physicochemical properties and tunable electronic structures. Research on GQDs has been booming over the past decades, and a number of excellent review articles have been provided on various other sensing principles of GQDs, such as fluorescence-based ion-sensing, bio-sensing, bio-imaging, and electrochemical, photoelectrochemical, and electrochemiluminescence sensing, and therapeutic, energy and catalysis applications. However, so far, there is no single review article on the application of GQDs in the field of chemiresistive gas sensing. This is our primary inspiration for writing this review, with a focus on the chemiresistive gas sensors reported using GQD-based composites. In this review, the various synthesized strategies of GQDs and its composites, gas sensing enhancement mechanisms, and the resulting sensing characteristics are presented. Finally, the current challenges and future prospects of GQDs in the abovementioned application filed have been discussed for the more rational design of advanced GQDs-based gas-sensing materials and innovative gas sensors with novel functionalities. [ABSTRACT FROM AUTHOR]

Compared with lever-type amplification mechanisms, bridge-type flexible amplification mechanisms have advantages in terms of amplification ratio and structural compactness. Therefore, they can effectively replace the lever-type amplification mechanism in the existing hair-like sensors and realize the development of miniature hair-like sensors with high sensitivity. With that in mind, a highly sensitive hair-like sensor based on a bridge-type amplification mechanism with distributed flexibility is presented to measure the airflow rate. First, the structural composition and operating principle of the hair-like sensor are described. Then, detailed design and analysis of the hair-like sensor are carried out, focusing on the design of the hair post structure, amplification mechanism, and resonator. Furthermore, the designed hair-like sensor is processed and prepared, and some experimental studies are conducted. The experimental results demonstrate that the developed hair-like sensor can measure the airflow rate with high sensitivity up to 8.56 Hz/(m/s)2. This provides a new concept for the structural design of hair-like sensors and expands the application of bridge-type flexible amplification mechanisms in the field of micro/nano sensors. [ABSTRACT FROM AUTHOR]

Novel food-grade bigels were fabricated using zein nanoparticles for interfacial stabilization and non-surfactant gelators (beeswax and tapioca) for bulk stabilization. The present study demonstrated the importance of interfacial stability for biphasic gels and sheds light on the roles of the gelation mechanism and the oil/water ratio of a bigel on its microstructure, physical properties, and digestion behaviors. The results indicated that it is not an easy task to realize homogenization and subsequent gelation in beeswax–tapioca biphasic systems, as no amphiphilic components existed. However, applying the binding of zein nanoparticles at the oil–water interface allowed us to produce a homogeneous and stable bigel (oil fraction reach 40%), which exhibited enhanced structural and functional properties. Oleogel structures play a crucial role in determining the deformation response of bigel systems. As the oil content increased, the mechanical strength and elastic properties of bigels were enhanced. In the meantime, clear bigel-type transitions were observed. In addition, the fabricated bigels were shown to be beneficial for delayed digestion, and the lowest degree of lipolysis could be found in bigel with 50% oleogel. [ABSTRACT FROM AUTHOR]

Developing natural product-based anti-cancer drugs/agents is a promising way to overcome the serious side effects and toxicity of traditional chemotherapeutics for cancer treatment. However, rapid assessment of the in vivo anti-cancer activities of natural products is a challenge. Alternatively, zebrafish are useful model organisms and perform well in addressing this challenging issue. Nowadays, a growing number of studies have utilized zebrafish models to evaluate the in vivo activities of natural compounds. Herein, we reviewed the application of zebrafish models for evaluating the anti-cancer activity and toxicity of natural products over the past years, summarized its process and benefits, and provided future outlooks for the development of natural product-based anti-cancer drugs. [ABSTRACT FROM AUTHOR]

Direct ethanol fuel cell (DEFC) has attracted wide attention due to its wide range of fuel sources, cleanliness, and high efficiency. However, the problems of low catalytic efficiency and poor catalyst stability still exist in DEFC catalysts, which restrict its rapid development. With chloroplatinic acid (H2PtCl6·6H2O) as the precursor, Polyvinylpyrrolidone (PVP) plays the role of surfactant, stabilizer, and reducing agent in the experiment. Glycine is the surface control agent and co-reducing agent. Pt high-index facets nanocatalyst was prepared with the one-pot hydrothermal method by adjusting the amount of PVP and glycine. X-Ray Diffraction (XRD), transmission electron microscope (TEM), and scanning electron microscope (SEM) were used to characterize the micro-structure of the nanocatalyst, and the influence of PVP and glycine on the synthesis of high-index facets catalyst was studied. The electrocatalytic performance of the catalyst was tested with an electrochemical workstation, and it was found that the performance of the prepared catalyst was better than that of the commercial catalyst. When the mass ratio of PVP and Pt was 50:1 and the molar ratio of glycine and Pt was 24:1, Pt nanocatalysts with {310}, {520} and {830} high exponential facets were prepared. The electrochemical test results showed that the peak current density of ethanol oxidation was 2.194 m2/g, and the steady-state current density was 0.241 mA/cm2, which was 5.7 times higher than that of commercial catalyst. The results of this paper show that due to the defects such as steps and kinks on the surface of the high-index facets, the active sites are increased, thus showing excellent electrocatalytic performance. This study provides a theoretical basis for the development and commercial application of high index facets nanocatalysts. [ABSTRACT FROM AUTHOR]

In this work, SnO2 nanoflowers were prepared by a simple one-step hydrothermal process. The morphology and structure of SnO2 nanoflowers were characterized by SEM, TEM, Raman spectroscopy, and XRD, which demonstrated the good crystallinity of the SnO2 tetrahedron structure of the as-synthesized materials. In addition, the sensing properties of SnO2 nanoflowers were studied in detail. It was found that the SnO2 nanoflower-based gas sensor exhibits excellent gas response (9.2 to 120 ppm), fast response and recovery (2/15 s to 6 ppm), good linearity of correlation between response (S) vs. concentration (C) (lgS = 0.505 lgC − 0.147, R2 = 0.9863), superb repeatability, and selectivity at 300 °C. The outstanding performance can also be attributed to the high specific surface area ratio and size of SnO2 nanoflowers close to the thickness of the electron depletion layer that can provide abundant active sites, promote the rate of interaction, and make it easier for gas molecules to diffuse into the interior of the material. Therefore, SnO2 nanoflowers can be an ideal sensing material for real-time monitoring of low-concentration HCHO. [ABSTRACT FROM AUTHOR]

Hydrogen (H2) sensors are of great significance in hydrogen energy development and hydrogen safety monitoring. However, achieving fast and effective detection of low concentrations of hydrogen is a key problem to be solved in hydrogen sensing. In this work, we combined the excellent gas sensing properties of tin(IV) oxide (SnO2) and zinc oxide (ZnO) with the outstanding electrical properties of reduced graphene oxide (rGO) and prepared palladium (Pd)-doped rGO/ZnO-SnO2 nanocomposites by a hydrothermal method. The crystal structure, structural morphology, and elemental composition of the material were characterized by FE-SEM, TEM, XRD, XPS, Raman spectroscopy, and N2 adsorption–desorption. The results showed that the Pd-doped ZnO-SnO2 composites were successfully synthesized and uniformly coated on the surface of the rGO. The hydrogen gas sensing performance of the sensor prepared in this work was investigated, and the results showed that, compared with the pure Pd-doped ZnO-SnO2 sensor, the Pd-doped rGO/ZnO-SnO2 sensor modified with 3 wt% rGO had better hydrogen (H2)-sensing response of 9.4–100 ppm H2 at 380 °C. In addition, this sensor had extremely low time parameters (the response time and recovery time for 100 ppm H2 at 380 °C were 4 s and 8 s, respectively) and an extremely low detection limit (50 ppb). Moreover, the sensor exhibited outstanding repeatability and restoration. According to the analysis of the sensing mechanism of this nanocomposite, the enhanced sensing performance of the Pd-doped rGO/ZnO-SnO2 sensor is mainly due to the heterostructure of rGO, ZnO, and SnO2, the excellent electrical and physical properties of rGO and the synergy between rGO and Pd. [ABSTRACT FROM AUTHOR]

Compound 1 (SMTP-7, also FGFC1), an isoindolone alkaloid from marine fungi Starchbotrys longispora FG216 and fungi Stachybotrys microspora IFO 30018, possessed diverse bioactivities such as thrombolysis, anti-inflammatory and anti-oxidative properties, and so on. It may be widely used for the treatment of various diseases, including cerebral infarction, stroke, ischemia/reperfusion damage, acute kidney injury, etc. Especially in cerebral infarction, compound 1 could reduce hemorrhagic transformation along with thrombolytic therapy, as the traditional therapies are accompanied with bleeding risks. In the latest studies, compound 1 selectively inhibited the growth of NSCLC cells with EGFR mutation, thus demonstrating its excellent anti-cancer activity. Herein, we summarized pharmacological activities, preparation of staplabin congeners—especially compound 1—and the mechanism of compound 1, with potential therapeutic applications. [ABSTRACT FROM AUTHOR]

To expand the range of daphnetin-based inhibitors/activators used for targeting G protein-coupled receptors (GPCRs) in disease treatment, twenty-five coumarin derivatives 1–25, including 7,8-dihydroxycoumarin and 7-hydroxycoumarin derivatives with various substitution patterns/groups at C3-/4- positions, were synthesized via mild Pechmann condensation and hydroxyl modification. The structures were characterized by 1H NMR, 13C NMR and ESI-MS. Their inhibition or activation activities relative to GPCRs were evaluated by double-antibody sandwich ELISA (DAS–ELISA) in vitro. The results showed that most of the coumarin derivatives possessed a moderate GPCR activation or inhibitory potency. Among them, derivatives 14, 17, 18, and 21 showed a remarkable GPCR activation potency, with EC50 values of 0.03, 0.03, 0.03, and 0.02 nM, respectively. Meanwhile, derivatives 4, 7, and 23 had significant GPCR inhibitory potencies against GPCRs with IC50 values of 0.15, 0.02, and 0.76 nM, respectively. Notably, the acylation of hydroxyl groups at the C-7 and C-8 positions of 7,8-dihydroxycoumarin skeleton or the etherification of the hydroxyl group at the C-7 position of the 7-hydroxycoumarin skeleton could successfully change GPCRs activators into inhibitors. This work demonstrated a simple and efficient approach to developing coumarin derivatives as remarkable GPCRs activators and inhibitors via molecular diversity-based synthesis. [ABSTRACT FROM AUTHOR]

Featured Application: New trends on marine biomaterials. The objective of this study is to innovatively evaluate the biochemistry performance of α-chitosan from Portunus trituberculatus shell and β-chitosan from Illex argentinus squid gladius by using the weighted composite index method, and provide a theoretical basis for better development and utilization of chitosan biomedical materials. To build a composite evaluation system, seven key indicators, including molecular weight (Mw), deacetylation degree (DD), water binding capacity (WBC), fat binding capacity (FBC), thermal stability (TS), primary structure and secondary structure, which significantly affect chitosan biochemical characteristics, were determined and analyzed. The viscosity average Mw of chitosan was in the range of 22.5–377.1 kDa, and the DD was 83.4–97.8%. Thermogravimetric (TG) and differential scanning calorimetry (DSC) analyses of commercial chitosan (CS), crab chitosan (CSC) and squid chitosan (CSS) showed a downward trend in TS, while WBC and FBC showed an obvious upward trend. FT-IR had a similar profile in peak shape, but the peak position slightly shifted. CD indicated that chitosan maintained the double helix structure and multiple secondary structural elements. The composite weighted index values of CS, CSC and CSS were 0.85, 0.94 and 1.31 respectively, which indicated that the CSS biochemistry performance was significantly better than CSC, and β-chitosan has great potential in biomedical materials. [ABSTRACT FROM AUTHOR]

The converter slag composition and the present situation on removal of phosphorus in converter slag are introduced. There are four dephosphorization processes from the converter slag, such as magnetic separation, density, leaching and reduction dephosphorization. By comparison, the effect of reducing dephosphorization is relatively preferable because simple and dephosphorization rate of up to 84%. The gasification dephosphorization rate is at range of 36% to 84% using different reductants at steelmaking temperature. [ABSTRACT FROM AUTHOR]

To improve the dispersion of carbon nanotubes (CNTs) and flame retardancy of layered double hydroxide (LDH) in epoxy resin (EP), organic nickel-iron layered double hydroxide (ONiFe-LDH-CNTs) hybrids were assembled through co-precipitation. These hybrids were further used as reinforcing filler in EP. EP/ONiFe-LDH-CNTs nanocomposites containing 4 wt% of ONiFe-LDH-CNTs with different ratios of ONiFe-LDH and CNTs were prepared by ultrasonic dispersion and program temperature curing. The structure and morphology of the obtained hybrids were characterized by different techniques. The dispersion of nanofillers in the EP matrix was observed by transmission electron microscopy (TEM). The results revealed a coexistence of exfoliated and intercalated ONiFe-LDH- CNTs in polymer matrix. Strong combination of the above nanofillers with the EP matrix provided an efficient thermal and flame retardant improvement for the nanocomposites. It showed that EP/ONiFe-LDH-CNTs nanocomposites exhibited superior flame retardant and thermal properties compared with EP. Such improved thermal properties could be attributed to the better homogeneous dispersion, stronger interfacial interaction, excellent charring performance of ONiFe-LDH and synergistic effect between ONiFe-LDH and CNTs. [ABSTRACT FROM AUTHOR]

Two new C19-diterpenoid alkaloids, 7,8-epoxy-franchetine ( 1) and N(19)-en-austroconitine A ( 2), were isolated from Aconitum iochanicum. Compound 1 was a new C19-diterpenoid alkaloid with a 7,8-epoxy unit. Their structures were elucidated by comprehensive spectroscopic analyses including UV, IR, MS, 1D and 2D NMR. Biological activity tests indicated that two new compounds exhibited inhibitory activity against nitric oxide ( NO) production in LPS-activated RAW264.7 macrophages. Compared with positive control, the two new compounds showed weak anti-inflammatory effects with the inhibition rate of 27.3% and 29.2%, respectively. [ABSTRACT FROM AUTHOR]

As a part of our continuing work to discover bioactive leading molecules from marine microorganism, ethyl acetate fraction of organic extract of the train Stachybotrys longispora FG216 showed fibrinolytic activity in our primary screen. The bioassay-guided purification of the active fractions resulted in isolation of a new isoindolone, FGFC2 ( 1) (FGFC2, Fungi fibrinolytic compound 2), together with two known compounds, LL-Z1272β ( 2) and ergosterol ( 3). The structure of compound 1 was elucidated by the spectral analysis of 1D (1H, 13C) NMR, 2D (COSY, HSQC, and HMBC) and ESI-MS. Three compounds were evaluated for fibrinolytic activities in vitro. Compared to FGFC1 (EC5047 µmol/L) as a reference drug, compound 1 and ergosterol ( 3) showed moderate fibrinolytic activities in vitro with EC50 values of 108.16 and 156.30 µmol/L, respectively. LL-Z1272β ( 2) had no fibrinolytic activity. [ABSTRACT FROM AUTHOR]