23 research outputs found

    Entrainer-Assisted Pressure-Swing Distillation for Separating the Minimum-Boiling Azeotrope Toluene/Pyridine: Design and Control

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    The separation of toluene/pyridine by distillation still remains an obstacle in industry because of not only the formation of a minimum-boiling azeotrope but also their relative volatilities, whose ratio is close to unity throughout the whole composition range. Extractive distillation is still not feasible because it is hard to find suitable entrainers. Heterogeneous azeotropic distillation might require high energy consumption to obtain both purified products. Conventional pressure-swing distillation is also not feasible. In this work, we apply entrainer-assisted pressure-swing distillation to separate toluene/pyridine (95 mol %/5 mol %) by introducing <i>n</i>-propanol as an entrainer. Based on the different compositions of the recycling stream sent back to the azeotropic column, a two-column sequence and a three-column sequence are established. Both sequences are partially heat-integrated. The steady-state designs of both sequences are optimized based on the total annual cost (TAC). The results reveal that the optimal two-column sequence has a 16.07% reduction of TAC and a 14.39% energy savings compared with the three-column sequence. Furthermore, the dynamic controllability of the two-column sequence is investigated by introducing ±10% disturbances in the feed flow rate and ±20% disturbances in the pyridine concentration. A conventional temperature control structure is implemented. As the fresh feed is quite dilute in pyridine, the purity of the pyridine product will be significantly influenced by even a small change in the recycling-stream flow rate. Therefore, the recycling-stream flow rate must be selected as a manipulated variable that is manipulated to control the pyridine product purity. The results reveal that robust control can be achieved

    Image_1_Effect of sarcopenia on survival in patients after pancreatic surgery: a systematic review and meta-analysis.TIF

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    BackgroundNumerous studies have reported sarcopenia to be associated with unfavorable outcomes in patients who have undergone pancreatectomy. Therefore, in this meta-analysis, we examined the relationship between sarcopenia and survival after pancreatic surgery.MethodsPubMed, Embase, and Cochrane Library were searched for studies that examined the association between sarcopenia and survival after pancreatic surgery from the inception of the database until June 1, 2023. Hazard ratio (HR) for overall survival (OS) and/or progression-free survival (PFS) of sarcopenia and pancreatic surgery were extracted from the selected studies and random or fixed-effect models were used to summarize the data according to the heterogeneity. Publication bias was assessed using Egger’s linear regression test and a funnel plot.ResultsSixteen studies met the inclusion criteria. For 13 aggregated univariate and 16 multivariate estimates, sarcopenia was associated with decreased OS (univariate analysis: HR 1.69, 95% CI 1.48–1.93; multivariate analysis: HR 1.69; 95% CI 1.39–2.05, I2 = 77.4%). Furthermore, sarcopenia was significantly associated with poor PFS of pancreatic resection (Change to univariate analysis: HR 1.74, 95% CI 1.47–2.05; multivariate analysis: HR 1.54; 95% CI 1.23–1.93, I2 = 63%).ConclusionSarcopenia may be a significant prognostic factor for a shortened survival following pancreatectomy since it is linked to an elevated risk of mortality. Further studies are required to understand how sarcopenia affects long-term results after pancreatic resection.Systematic review registrationRegistration ID: CRD42023438208 https://www.crd.york.ac.uk/PROSPERO/#recordDetails.</p

    Image_4_Effect of sarcopenia on survival in patients after pancreatic surgery: a systematic review and meta-analysis.TIF

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    BackgroundNumerous studies have reported sarcopenia to be associated with unfavorable outcomes in patients who have undergone pancreatectomy. Therefore, in this meta-analysis, we examined the relationship between sarcopenia and survival after pancreatic surgery.MethodsPubMed, Embase, and Cochrane Library were searched for studies that examined the association between sarcopenia and survival after pancreatic surgery from the inception of the database until June 1, 2023. Hazard ratio (HR) for overall survival (OS) and/or progression-free survival (PFS) of sarcopenia and pancreatic surgery were extracted from the selected studies and random or fixed-effect models were used to summarize the data according to the heterogeneity. Publication bias was assessed using Egger’s linear regression test and a funnel plot.ResultsSixteen studies met the inclusion criteria. For 13 aggregated univariate and 16 multivariate estimates, sarcopenia was associated with decreased OS (univariate analysis: HR 1.69, 95% CI 1.48–1.93; multivariate analysis: HR 1.69; 95% CI 1.39–2.05, I2 = 77.4%). Furthermore, sarcopenia was significantly associated with poor PFS of pancreatic resection (Change to univariate analysis: HR 1.74, 95% CI 1.47–2.05; multivariate analysis: HR 1.54; 95% CI 1.23–1.93, I2 = 63%).ConclusionSarcopenia may be a significant prognostic factor for a shortened survival following pancreatectomy since it is linked to an elevated risk of mortality. Further studies are required to understand how sarcopenia affects long-term results after pancreatic resection.Systematic review registrationRegistration ID: CRD42023438208 https://www.crd.york.ac.uk/PROSPERO/#recordDetails.</p

    Image_2_Effect of sarcopenia on survival in patients after pancreatic surgery: a systematic review and meta-analysis.TIF

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    BackgroundNumerous studies have reported sarcopenia to be associated with unfavorable outcomes in patients who have undergone pancreatectomy. Therefore, in this meta-analysis, we examined the relationship between sarcopenia and survival after pancreatic surgery.MethodsPubMed, Embase, and Cochrane Library were searched for studies that examined the association between sarcopenia and survival after pancreatic surgery from the inception of the database until June 1, 2023. Hazard ratio (HR) for overall survival (OS) and/or progression-free survival (PFS) of sarcopenia and pancreatic surgery were extracted from the selected studies and random or fixed-effect models were used to summarize the data according to the heterogeneity. Publication bias was assessed using Egger’s linear regression test and a funnel plot.ResultsSixteen studies met the inclusion criteria. For 13 aggregated univariate and 16 multivariate estimates, sarcopenia was associated with decreased OS (univariate analysis: HR 1.69, 95% CI 1.48–1.93; multivariate analysis: HR 1.69; 95% CI 1.39–2.05, I2 = 77.4%). Furthermore, sarcopenia was significantly associated with poor PFS of pancreatic resection (Change to univariate analysis: HR 1.74, 95% CI 1.47–2.05; multivariate analysis: HR 1.54; 95% CI 1.23–1.93, I2 = 63%).ConclusionSarcopenia may be a significant prognostic factor for a shortened survival following pancreatectomy since it is linked to an elevated risk of mortality. Further studies are required to understand how sarcopenia affects long-term results after pancreatic resection.Systematic review registrationRegistration ID: CRD42023438208 https://www.crd.york.ac.uk/PROSPERO/#recordDetails.</p

    Table_1_Effect of sarcopenia on survival in patients after pancreatic surgery: a systematic review and meta-analysis.docx

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    BackgroundNumerous studies have reported sarcopenia to be associated with unfavorable outcomes in patients who have undergone pancreatectomy. Therefore, in this meta-analysis, we examined the relationship between sarcopenia and survival after pancreatic surgery.MethodsPubMed, Embase, and Cochrane Library were searched for studies that examined the association between sarcopenia and survival after pancreatic surgery from the inception of the database until June 1, 2023. Hazard ratio (HR) for overall survival (OS) and/or progression-free survival (PFS) of sarcopenia and pancreatic surgery were extracted from the selected studies and random or fixed-effect models were used to summarize the data according to the heterogeneity. Publication bias was assessed using Egger’s linear regression test and a funnel plot.ResultsSixteen studies met the inclusion criteria. For 13 aggregated univariate and 16 multivariate estimates, sarcopenia was associated with decreased OS (univariate analysis: HR 1.69, 95% CI 1.48–1.93; multivariate analysis: HR 1.69; 95% CI 1.39–2.05, I2 = 77.4%). Furthermore, sarcopenia was significantly associated with poor PFS of pancreatic resection (Change to univariate analysis: HR 1.74, 95% CI 1.47–2.05; multivariate analysis: HR 1.54; 95% CI 1.23–1.93, I2 = 63%).ConclusionSarcopenia may be a significant prognostic factor for a shortened survival following pancreatectomy since it is linked to an elevated risk of mortality. Further studies are required to understand how sarcopenia affects long-term results after pancreatic resection.Systematic review registrationRegistration ID: CRD42023438208 https://www.crd.york.ac.uk/PROSPERO/#recordDetails.</p

    Obtaining Reversible, Durable, High-Contrast Photochromism and Antibacterial Properties in a Flexible, Wearable Fiber Using Nanometer-Sized Polyoxotungstate

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    An approach to preparing a functional fiber has been developed. The method is carried out to link nanometer-sized polyoxometalate and cotton fabric by employing a cationic agent. Interestingly, the composite fabric exhibits a broad absorption peak in the visible range after irradiation, accompanied by obvious color changes from white to blue owing to electron transfer. The W(VI) transforms into a heteropoly blue W(V) rapidly (<5 s) in response to UV irradiation with a low-power UV (5 W), whereas its recovery seems slightly slow (5 h) in the air. Nevertheless, increasing the temperature can accelerate the fading process. Further, the continuous coloring–fading process presents outstanding repetition stability. Additionally, the composite fabric shows a degree of antibacterial property. Meanwhile, the physical properties indicate that multifunctional cotton retains natural features after chemical modification. In a word, the reversible photoresponsive cellulose fabric can be a promising candidate for developing a wearable and flexible sensor to monitor environmental changes

    Image_3_Effect of sarcopenia on survival in patients after pancreatic surgery: a systematic review and meta-analysis.TIF

    No full text
    BackgroundNumerous studies have reported sarcopenia to be associated with unfavorable outcomes in patients who have undergone pancreatectomy. Therefore, in this meta-analysis, we examined the relationship between sarcopenia and survival after pancreatic surgery.MethodsPubMed, Embase, and Cochrane Library were searched for studies that examined the association between sarcopenia and survival after pancreatic surgery from the inception of the database until June 1, 2023. Hazard ratio (HR) for overall survival (OS) and/or progression-free survival (PFS) of sarcopenia and pancreatic surgery were extracted from the selected studies and random or fixed-effect models were used to summarize the data according to the heterogeneity. Publication bias was assessed using Egger’s linear regression test and a funnel plot.ResultsSixteen studies met the inclusion criteria. For 13 aggregated univariate and 16 multivariate estimates, sarcopenia was associated with decreased OS (univariate analysis: HR 1.69, 95% CI 1.48–1.93; multivariate analysis: HR 1.69; 95% CI 1.39–2.05, I2 = 77.4%). Furthermore, sarcopenia was significantly associated with poor PFS of pancreatic resection (Change to univariate analysis: HR 1.74, 95% CI 1.47–2.05; multivariate analysis: HR 1.54; 95% CI 1.23–1.93, I2 = 63%).ConclusionSarcopenia may be a significant prognostic factor for a shortened survival following pancreatectomy since it is linked to an elevated risk of mortality. Further studies are required to understand how sarcopenia affects long-term results after pancreatic resection.Systematic review registrationRegistration ID: CRD42023438208 https://www.crd.york.ac.uk/PROSPERO/#recordDetails.</p

    Multiple Steady-States Analysis and Unstable Operating Point Stabilization in Homogeneous Azeotropic Distillation with Intermediate Entrainer

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    The steady-state multiplicity in azeotropic distillation processes has been theoretically predicted and verified experimentally for decades. However, it is a tough task to detect all the steady-state solutions. The purpose of this article is 2-fold: first, it provides a systematical study on the multiplicity in homogeneous azeotropic distillation with intermediate entrainer and a novel strategy is proposed to find all the steady-state solutions using “Design Specs/Vary” in Aspen Plus. Operating on the unstable steady-state branch benefits both energy saving and reducing capital investment with the product quality specified. Because of the great benefits that operating on the unstable steady-state branch offers, the second purpose is to present suitable control schemes to stabilize the operating point on the unstable steady-state branch to achieve robust control

    Kaplan-Meier analysis of disease-free survival (DFS) in renal cell carcinoma according to expression of the EZH2 or H3K27me3 score.

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    <p>(A), (D) all patients in the training set. (B), (E) patients with I+II stage disease in the training set. (C), (F) patients with III+IV stage disease in the training set. (G), (J) all patients in the validation set. (H), (K) patients with I+II stage disease in the validation set. (I), (L) patients with III+IV stage disease in the validation set. </p

    Spinel (Mn, Fe)<sub>3</sub>O<sub>4</sub> Nanocatalyst for the Catalytic Ozone Decomposition under Humid Conditions

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    The development of ozone-decomposition catalysts with high efficiency and exceptional resistance to humidity is a significant challenge, as ozone is a primary air pollutant. This study successfully synthesized a series of MnxFe3–xO4 catalysts with varying crystal structures by adjusting the Mn/Fe molar ratios through a coprecipitation method with inorganic salt precursors. Compared to crystalline Mn3O4 and Fe2O3, the obtained amorphous MnFe2O4(MnFe-1) nanocatalyst exhibited an optimal ozone conversion rate of 99.9% for 50 ppm O3 with a space velocity (SV) of 600 L g–1 h–1 in dry gas and 77.4% for 50 ppm O3 with a SV of 600 L g–1 h–1 under a relative humidity (RH) of 60%. The superior performance of the amorphous sample can be attributed not only to its smaller size and larger surface area but also to the presence of Mn3+ as the active site, a higher number of oxygen vacancies and acid sites, and the synergistic effect between iron and manganese. This research offers a universally applicable preparation method for nanosized spinel oxides and provides an in-depth exploration of the ozone-decomposition mechanism
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