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1.
Angew Chem Int Ed Engl ; 62(49): e202313522, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-37855722

RESUMEN

Electrochemical carbon dioxide reduction reaction (CO2 RR) to produce valuable chemicals is a promising pathway to alleviate the energy crisis and global warming issues. However, simultaneously achieving high Faradaic efficiency (FE) and current densities of CO2 RR in a wide potential range remains as a huge challenge for practical implements. Herein, we demonstrate that incorporating bismuth-based (BH) catalysts with L-histidine, a common amino acid molecule of proteins, is an effective strategy to overcome the inherent trade-off between the activity and selectivity. Benefiting from the significantly enhanced CO2 adsorption capability and promoted electron-rich nature by L-histidine integrity, the BH catalyst exhibits excellent FEformate in the unprecedented wide potential windows (>90 % within -0.1--1.8 V and >95 % within -0.2--1.6 V versus reversible hydrogen electrode, RHE). Excellent CO2 RR performance can still be achieved under the low-concentration CO2 feeding (e.g., 20 vol.%). Besides, an extremely low onset potential of -0.05 VRHE (close to the theoretical thermodynamic potential of -0.02 VRHE ) was detected by in situ ultraviolet-visible (UV-Vis) measurements, together with stable operation over 50 h with preserved FEformate of ≈95 % and high partial current density of 326.2 mA cm-2 at -1.0 VRHE .

2.
Molecules ; 28(7)2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37049737

RESUMEN

Intelligent polymers have become the focus of attention worldwide. Intelligent polymer materials through organic synthesis methods are used to make inanimate organic materials become "feeling" and "sentient". Intelligent polymer materials have been applied in actual engineering production, and they are becoming a new research topic for scientists in various fields and countries, especially in the areas of drilling and plugging. The development of intelligent polymer materials can provide new solutions and technical means for drilling and plugging. Unlike traditional plugging materials, intelligent polymer plugging materials can cope with environmental changes. They have the characteristics of a strong target, good plugging effect, and no damage to the reservoir. However, there are currently no reviews on intelligent polymer plugging materials in the drilling field, so this paper fills that gap by reviewing the research progress of intelligent polymer plugging materials. In addition, this paper describes the mechanism and application status of intelligent polymer shape-memory polymers, intelligent polymer gels, intelligent polymer membranes, and intelligent polymer bionic materials in drilling and plugging. It is also pointed out that some intelligent polymer plugging materials still have problems, such as insufficient toughness and a poor resistance to salt and high temperature. At the same time, some suggestions for future research directions are also presented for reference.

3.
Molecules ; 28(3)2023 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-36770949

RESUMEN

Betaine is a new surfactant with good application prospects in high-temperature and high-salinity reservoirs. The interfacial properties of two kinds of betaine mixtures with a good synergistic effect were evaluated in this paper. On this basis, the effects of temperature-resistant, salt-resistant polymers with different contents of 2-acrylamide-2-methylpropanesulfonic acid (AMPS) on dynamic interfacial tensions (IFTs) against n-alkanes and crude oil were studied. The experimental results show that the IFTs between betaine ASB and n-alkanes can be reduced to ultra-low values by compounding with anionic surfactant petroleum sulfonate (PS) and extended anionic surfactant alkoxyethylene carboxylate (AEC), respectively. ASB@AEC is very oil-soluble with nmin value ≥14, and ASB@PS is relatively water-soluble with nmin value of 10. The water solubility of both ASB@PS and ASB@AEC is enhanced by the addition of water-soluble polymers. The HLB of the ASB@AEC solution becomes better against crude oil after the addition of polymers, and the IFT decreases to an ultra-low value as a result. On the contrary, the antagonistic effect in reducing the IFT can be observed for ASB@PS in the same case. In a word, polymers affect the IFTs of surfactant solutions by regulating the HLB.

4.
Zhongguo Zhong Yao Za Zhi ; 42(6): 1043-1047, 2017 Mar.
Artículo en Chino | MEDLINE | ID: mdl-29027414

RESUMEN

Quality by design (QbD) highlights the concept of "begin with the end", which means to thoroughly understand the target product quality first, and then guide pharmaceutical process development and quality control throughout the whole manufacturing process. In this paper, the Ginkgo biloba granules intermediates were taken as the research object, and the requirements of the tensile strength of tablets were treated as the goals to establish the methods for identification of granules' critical quality attributes (CQAs) and establishment of CQAs' limits. Firstly, the orthogonal partial least square (OPLS) model was adopted to build the relationship between the micromeritic properties of 29 batches of granules and the tensile strength of ginkgo leaf tablets, and thereby the potential critical quality attributes (pCQAs) were screened by variable importance in the projection (VIP) indexes. Then, a series of OPLS models were rebuilt by reducing pCQAs variables one by one in view of the rule of VIP values from low to high in sequence. The model performance results demonstrated that calibration and predictive performance of the model had no decreasing trend after variables reduction. In consideration of the results from variables selection as well as the collinearity test and testability of the pCQAs, the median particle size (D50) and the bulk density (Da) were identified as critical quality attributes (CQAs). The design space of CQAs was developed based on a multiple linear regression model established between the CQAs (D50 and Da) and the tensile strength. The control constraints of the CQAs were determined as 170 µm< D50<500 µm and 0.30 g•cm⁻³

Asunto(s)
Medicamentos Herbarios Chinos/normas , Ginkgo biloba/química , Análisis de los Mínimos Cuadrados , Tamaño de la Partícula , Control de Calidad , Comprimidos , Tecnología Farmacéutica
5.
Zhongguo Zhong Yao Za Zhi ; 42(6): 1037-1042, 2017 Mar.
Artículo en Chino | MEDLINE | ID: mdl-29027413

RESUMEN

In this paper, the granules intermediate prepared from the wet granulation process of ginkgo leaf tablet were taken as the research object, and then the stackability, homogeneity, flowability, compressibility and stability of granules were characterized by using micromeritics evaluation method. The physical fingerprint of granules were constructed by 16 indexes including bulk density, tapped density, span, width, relative homogeneity index, aspect ratio, Hausner ratio, angle of repose, granule flow time, inter-particle porosity, Carr index, specific surface area, pore volume, pore size distribution, loss on drying and hygroscopicity. Furthermore, compressibility parameters (i.e. index of parameter, index of parametric profile and index of good compression) were employed to analyze the compressibility characteristics of the granules. Two principal components (first principal component representing dimension parameter and second principal component representing morphology parameter), could be extracted from the physical fingerprint by the principal component analysis (PCA). The granules' physical fingerprint is of great importance to evaluate the batch-to-batch quality consistency of Ginkgo biloba granules and analyze the potential impacts of granules' quality attributes on product quality, which can provide guidance for the granules' quality control and process development..


Asunto(s)
Medicamentos Herbarios Chinos/normas , Ginkgo biloba/química , Desecación , Tamaño de la Partícula , Polvos , Control de Calidad , Comprimidos , Humectabilidad
6.
Zhongguo Zhong Yao Za Zhi ; 42(6): 1048-1054, 2017 Mar.
Artículo en Chino | MEDLINE | ID: mdl-29027415

RESUMEN

In this paper, under the guidance of quality by design (QbD) concept, the control strategy of the high shear wet granulation process of the ginkgo leaf tablet based on the design space was established to improve the process controllability and product quality consistency. The median granule size (D50) and bulk density (Da) of granules were identified as critical quality attributes (CQAs) and potential critical process parameters (pCPPs) were determined by the failure modes and effect analysis (FMEA). The Plackeet-Burmann experimental design was used to screen pCPPs and the results demonstrated that the binder amount, the wet massing time and the wet mixing impeller speed were critical process parameters (CPPs). The design space of the high shear wet granulation process was developed within pCPPs range based on the Box-Behnken design and quadratic polynomial regression models. ANOVA analysis showed that the P-values of model were less than 0.05 and the values of lack of fit test were more than 0.1, indicating that the relationship between CQAs and CPPs could be well described by the mathematical models. D50 could be controlled within 170 to 500 µm, and the bulk density could be controlled within 0.30 to 0.44 g•cm⁻³ by using any CPPs combination within the scope of design space. Besides, granules produced by process parameters within the design space region could also meet the requirement of tensile strength of the ginkgo leaf tablet..


Asunto(s)
Medicamentos Herbarios Chinos/normas , Ginkgo biloba/química , Tamaño de la Partícula , Control de Calidad , Comprimidos , Tecnología Farmacéutica
7.
Zhongguo Zhong Yao Za Zhi ; 42(6): 1055-1061, 2017 Mar.
Artículo en Chino | MEDLINE | ID: mdl-29027416

RESUMEN

Raw materials' quality variation could affect the quality consistency of product and the clinical efficacy. In this paper, the high shear wet granulation (HSWG) process of the ginkgo leaf tablet was taken as the research object. Ginkgo biloba extracts and excipients microcrystalline cellulose collected from various sources and batches were used to simulate raw materials' quality variation. Real-time torque was recorded to analyze the viscosity of the wetting mass, and then by combining with physical fingerprint, the impact of physical quality variation of powders on granule properties could be investigated. Based on regime map thesis, whether the granules' nucleation mode was in mechanical dispersion regime was determined by calculating dimensionless parameters, which would lead to the unstable output in considerations of granule yield ratio and particle size distribution (PSD) curve. The orthogonal partial least square (OPLS) model was adopted to build the relationship between the micromeritic properties and the mediangranule size (D50) of Ginkgo biloba granules and then the critical material attributes (CMAs) were screened by variable importance in the projection (VIP) indexes. The results demonstrated that the properties of powders including hygroscopicity, angle of repose, Hausner ratio, Carr index, D10 and loss on drying affected the granule size. Besides, Ginkgo biloba granules were compressed into tablets. In view of tensile strength analysis, the raw materials' quality variation did not result in decrease of tensile strength of the ginkgo leaf tablets. The design space of critical quality attributes (CQAs) and the process design space which could cope with raw materials' quality variation were proved to be robust..


Asunto(s)
Medicamentos Herbarios Chinos/normas , Ginkgo biloba/química , Celulosa , Composición de Medicamentos , Excipientes , Tamaño de la Partícula , Polvos , Control de Calidad , Comprimidos , Tecnología Farmacéutica
8.
Artículo en Inglés | MEDLINE | ID: mdl-27404670

RESUMEN

This study presented a new strategy of overall uncertainty measurement for near infrared (NIR) quantitative analysis of cryptotanshinone in tanshinone extract powders. The overall uncertainty of NIR analysis from validation data of precision, trueness and robustness study was fully investigated and discussed. Quality by design (QbD) elements, such as risk assessment and design of experiment (DOE) were utilized to organize the validation data. An "I×J×K" (series I, the number of repetitions J and level of concentrations K) full factorial design was used to calculate uncertainty from the precision and trueness data. And a 2(7-4) Plackett-Burmann matrix with four different influence factors resulted from the failure mode and effect analysis (FMEA) analysis was adapted for the robustness study. The overall uncertainty profile was introduced as a graphical decision making tool to evaluate the validity of NIR method over the predefined concentration range. In comparison with the T. Saffaj's method (Analyst, 2013, 138, 4677.) for overall uncertainty assessment, the proposed approach gave almost the same results, demonstrating that the proposed method was reasonable and valid. Moreover, the proposed method can help identify critical factors that influence the NIR prediction performance, which could be used for further optimization of the NIR analytical procedures in routine use.


Asunto(s)
Abietanos/análisis , Fenantrenos/análisis , Extractos Vegetales/química , Espectroscopía Infrarroja Corta , Incertidumbre , Análisis de Varianza , Calibración , Cromatografía Líquida de Alta Presión , Reproducibilidad de los Resultados
9.
Drug Des Devel Ther ; 10: 3909-3924, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27932865

RESUMEN

The quality of Chinese herbal medicine tablets suffers from batch-to-batch variability due to a lack of manufacturing process understanding. In this paper, the Panax notoginseng saponins (PNS) immediate release tablet was taken as the research subject. By defining the dissolution of five active pharmaceutical ingredients and the tablet tensile strength as critical quality attributes (CQAs), influences of both the manipulated process parameters introduced by an orthogonal experiment design and the intermediate granules' properties on the CQAs were fully investigated by different chemometric methods, such as the partial least squares, the orthogonal projection to latent structures, and the multiblock partial least squares (MBPLS). By analyzing the loadings plots and variable importance in the projection indexes, the granule particle sizes and the minimal punch tip separation distance in tableting were identified as critical process parameters. Additionally, the MBPLS model suggested that the lubrication time in the final blending was also important in predicting tablet quality attributes. From the calculated block importance in the projection indexes, the tableting unit was confirmed to be the critical process unit of the manufacturing line. The results demonstrated that the combinatorial use of different multivariate modeling methods could help in understanding the complex process relationships as a whole. The output of this study can then be used to define a control strategy to improve the quality of the PNS immediate release tablet.


Asunto(s)
Composición de Medicamentos/métodos , Medicamentos Herbarios Chinos/análisis , Medicamentos Herbarios Chinos/farmacología , Panax notoginseng/química , Medicamentos Herbarios Chinos/química , Modelos Estadísticos , Comprimidos
10.
Zhongguo Zhong Yao Za Zhi ; 41(5): 823-829, 2016 Mar.
Artículo en Chino | MEDLINE | ID: mdl-28875634

RESUMEN

The near-infrared (NIR) spectroscopy for offline monitoring of alcohol extraction process of Salvia miltiorrhiza was investigated, with high performance liquid chromatography (HPLC) determination of value for reference. The partial least squares method was adopted to establish the tanshinone ⅡA quantitative calibration model, so as to detect extraction process of Salvia miltiorrhiza. Because the differences between batches of raw materials may endanger the robustness of the original model, the simple interval calculation (SIC) was applied in updating the near-infrared quantitative model for traditional Chinese medicine extraction process for the first time, and compared with Random Selection (RS) method. SIC's final updating results showed that root mean square with cross validation (RMSECV), root mean square error of prediction (RMSEP) and residual predictive deviation (RPD) of tanshinone ⅡA were 0.006 8 g•L⁻¹, 0.005 4 g•L⁻¹ and 3.14, respectively; but RS' final updating results showed that RMSECV, RMSEP and RPD were 0.006 4 g•L⁻¹, 0.006 8 g•L⁻¹ and 2.50, respectively. This study suggested that SIC is superior to RS, and provided a research foundation for quality control and monitoring of S. miltiorrhiza extraction process in the future.


Asunto(s)
Medicamentos Herbarios Chinos/química , Salvia miltiorrhiza/química , Espectroscopía Infrarroja Corta/métodos , Abietanos/química , Abietanos/aislamiento & purificación , Algoritmos , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos/aislamiento & purificación , Control de Calidad
11.
Yao Xue Xue Bao ; 50(3): 355-9, 2015 Mar.
Artículo en Chino | MEDLINE | ID: mdl-26118117

RESUMEN

The design space of the high shear wet granulation process was established and validated within the framework of quality by design (QbD). The system of microcrystalline cellulose-de-ioned water was used in this study. The median granule size and bulk density of granules were identified as critical quality attributes. Plackeet-Burmann experimental design was used to screen these factors as follows: dry mixing time, the impeller and chopper speed of dry mixing, water amount, water addition time, wet massing time, the impeller and chopper speed of wet massing and drying time. And the optimization was implemented with the central composite experimental design based on screened critical process parameters. The design space of the high shear wet granulation process was established based on the quadratic polynomial regression model. Since the P-values of both models were less than 0.05 and values of lack of fit were more than 0.1, the relationship between critical quality attributes and critical process parameters could be well described by the two models. The reliability of design space, illustrated by overlay plot, was improved with the addition of 95% confidence interval. For those granules whose process parameters were in the design space, the granule size could be controlled within 250 to 355 µm, and the bulk density could be controlled within a range of 0.4 to 0.6 g x cm(-3). The robustness and flexibility of the high shear wet granulation process have been enhanced via the establishment of the design space based on the QbD concept.


Asunto(s)
Celulosa/química , Tecnología Farmacéutica/métodos , Reproducibilidad de los Resultados , Agua
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