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Biomass-based polymers and their property regulation using functional materials have attracted much interest. In this work, ricinoleic acid-derived cyclic carbonate was prepared and applied to the synthesis of nonisocyanate polyurethane (NIPU) with aliphatic diamine, in which octa(aminopropyl) polyhedral oligomeric silsesquioxane (OAP-POSS) was incorporated as polyamine to partially or totally substitutes for the diamine to introduce POSS units into the polymer thus regulating the properties of the resultant material. In the curing process, Fourier transform infrared spectroscopy (FT-IR) was used to track the reaction and curing at 50[degrees]C for 12 h was found to be sufficient for the polymerization. A series of POSS modified NIPUs were obtained by altering the molar fraction of OAP-POSS in total amine components and the material with the highest thermal stability, shore hardness and water resistance was accessed with 100% substitution of OAP-POSS for diamine. KEYWORDS biomass utilization, nonisocyanate polyurethanes, POSS modification, ricinoleic acid, 1 | INTRODUCTION The excessive consumption of fossil fuels has led to massive carbon dioxide emissions, resulting in global warming and consequent detrimental environmental impacts. [1] Moreover, fossil resources are [...]

Monitoring the degradation state of hydraulic pumps is of great significance to the safe and stable operation of equipment. As an important step, feature extraction has always been challenging. The non-stationary and nonlinear characteristics of vibration signals are likely to weaken the performance of traditional features. The two-dimensional image representation of vibration signals can provide more information for feature extraction, but it is challenging to obtain sufficient information based on small-size images. To solve these problems, a method for feature extraction based on modified hierarchical decomposition (MHD) and image processing is proposed in this paper. First, a set of signals decomposed by MHD are converted into gray-scale images. Second, features from accelerated segment test (FAST) algorithm are applied to detecting the feature points of the gray-scale image. Third, the real part of Gabor filter bank is used to convolve the images, and the responses of feature points are used to calculate histograms that are regarded as feature vectors. The method for feature extraction fully acquires the multi-layered texture information of small-size images and removes the redundant information. Furthermore, support vector machine (SVM) and nondominated sorting genetic algorithm II (NSGA-II) are introduced to conduct feature selection and state identification. NSGA-II and SVM can conduct the joint optimization of these two goals. The details of the proposed method are validated using experimental data, and the results show that the highest recognition rate of our proposed method can reach 100%. The results of the comparison among the proposed method, local binary pattern (LBP), and one-dimensional ternary patterns (1D-TPs) certify the superiorities of the proposed method. It obtains the highest classification accuracy (99.7%–98%) and the lowest feature set dimension (13–10). [ABSTRACT FROM AUTHOR]

Bio‐derived lubricants, especially those derived from vegetable oils, are considered to be promising alternatives to mineral oil‐based lubricants due to the features of sustainability and environmental friendliness. In this work, the polyol ricinoleates were prepared by esterification of ricinoleic acid with trimethylolpropane (TMP), neopentyl glycol (NPG) and pentaerythritol (PE) respectively using Lewis acidic stannous oxide as an efficient heterogeneous catalyst, affording the polyol ricinoleates up to 99.7% yield. Remarkably, the solid catalyst was readily recovered and reused at least for five cycles without significant loss of activity. The resulting polyol ricinoleates products were structurally characterized by Fourier transform infrared spectroscopy (FT‐IR), 1H NMR, 13C NMR, electrospray ionization mass spectra (ESI‐MS); and were stable below 300°C through thermogravimetric analysis (TGA). Furthermore, the physicochemical and lubricating properties of as‐synthesized polyol esters were also evaluated including viscosity at 40 and 100°C, viscosity index (VI), pour point and flash point, thermal stability and wear scar diameter. To our delight, the performance indicators of the target products were comparable or better than the commercial lubricants, showing their potential as lubricant base oil. This work represents an alternative access to useful lubricant products via effective and selective conversion of non‐edible vegetable oil. [ABSTRACT FROM AUTHOR]

Background: Delirium is a neuropsychiatric syndrome characterized by acute disturbances of consciousness with rapid onset, rapid progression, obvious fluctuations, and preventable, reversible, and other characteristics. Patients with delirium in the intensive care unit (ICU) are often missed or misdiagnosed and do not receive adequate attention., Aim: To analyze the risk factors for delirium in ICU patients and explore the application of emotional nursing with pain nursing in the management of delirium., Methods: General data of 301 critically ill patients were retrospectively collected, including histories (cardiovascular and cerebrovascular diseases, hypertension, smoking, alcoholism, and diabetes), age, sex, diagnosis, whether surgery was performed, and patient origin (emergency/clinic). Additionally, the duration of sedation, Richmond Agitation Sedation Scale score, combined emotional and pain care, ventilator use duration, vasoactive drug use, drainage tube retention, ICU stay duration, C-reactive protein, procalcitonin, white blood cell count, body temperature, Acute Physiology and Chronic Health Evaluation II (APACHE II) score, and Sequential Organ Failure Assessment score were recorded within 24 h after ICU admission. Patients were assessed for delirium according to confusion assessment method for the ICU, and univariate and multivariate logistic regression analyses were performed to identify the risk factors for delirium in the patients., Results: Univariate logistic regression analysis was performed on the 24 potential risk factors associated with delirium in ICU patients. The results showed that 16 risk factors were closely related to delirium, including combined emotional and pain care, history of diabetes, and patient origin. Multivariate logistic regression analysis revealed that no combined emotional and pain care, history of diabetes, emergency source, surgery, long stay in the ICU, smoking history, and high APACHE II score were independent risk factors for delirium in ICU patients., Conclusion: Patients with diabetes and/or smoking history, postoperative patients, patients with a high APACHE II score, and those with emergency ICU admission need emotional and pain care, flexible visiting modes, and early intervention to reduce delirium incidence., Competing Interests: Conflict-of-interest statement: The authors declare no conflict of interest for this article., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

The escalating rate of fossil fuel combustion contributes to excessive CO 2 emission and the resulting global climate change has drawn considerable attention. Therefore, tremendous efforts have been devoted to mitigate the CO 2 accumulation in the atmosphere. Carbon capture and storage (CCS) strategy has been regarded as one of the promising options for controlling CO 2 build-up. However, desorption and compression of CO 2 need extra energy input. To circumvent this energy issue, carbon capture and utilization (CCU) strategy has been proposed whereby CO 2 can be captured and in situ activated simultaneously to participate in the subsequent conversion under mild conditions, offering valuable compounds. As an alternative to CCS, the CCU has attracted much concern. Although various absorbents have been developed for the CCU strategy, the direct, in situ chemical conversion of the captured CO 2 into valuable chemicals remains in its infancies compared with the gaseous CO 2 conversion. This review summarizes the recent progress on CO 2 capture and in situ catalytic transformation. The contents are introduced according to the absorbent types, in which different reaction type is involved and the transformation mechanism of the captured CO 2 and the role of the absorbent in the conversion are especially elucidated. We hope this review can shed light on the transformation of the captured CO 2 and arouse broad concern on the CCU strategy.