基于CAPE-OPEN标准的简捷炼油过程建模及常减压蒸馏流程在线模拟

简捷炼油过程模型广泛应用于运行监测、在线计算、实时优化等领域,但大多数模型只是将输入、输出变量进行关联,无法计算出各组分流量组成,难以集成在模拟软件中进行全流程模拟。本研究简化了炼油分离过程,开发了基于CAPE-OPEN标准的简捷炼油塔模型。首先,将炼油过程简化为连续的分离单元,根据实际产品数据校正模型参数,实现某一实际工况流程模拟;其次,将模型参数与实际工况操作变量数据相结合,采用径向基函数插值确定操作变量对模型参数的影响关系,实现多种工况流程模拟;最后,通过常减压蒸馏工业装置实例的3种工况进行验证。结果表明:各工况模拟结果与Aspen计算结果相比,初馏塔塔顶油馏出温度点偏差大多在2%以内,常减压蒸馏塔各侧线油的馏出温度点平均偏差在3%以内;与实际结果相比,平均误差都在5%以内,符合工程允许误差范围要求。所建模型的计算速度快,各塔均在0.2 s左右完成计算,适用于在线生产、调度等。

基于CAPE-OPEN标准的乙苯脱氢反应器模块开发与全流程模拟

基于某乙苯负压绝热脱氢制苯乙烯装置转化率低于设计值的现状,建立了包括小分子水蒸气转化反应在内的乙苯绝热脱氢制苯乙烯反应动力学模型和反应器模型,基于工业数据,估计了模型动力学参数,模型具有较高的精度;采用C++语言和COM技术开发了符合CAPE-OPEN标准的乙苯脱氢制苯乙烯反应器单元模块;在Aspen Plus平台构建了内嵌反应器模块的乙苯脱氢制苯乙烯全流程模型,反应器与精馏塔的模拟结果与实际相吻合;进一步考察了工艺参数对装置运行中期反应的影响,提出了适宜的工艺参数,为乙苯脱氢制苯乙烯的工艺设计、生产优化提供有益的支持。

The impact of the Rural Minimum Living Standard Guarantee(Rural Dibao)Program on child nutrition outcomes

The Rural Minimum Living Standard Guarantee(Rural Dibao)is an important unconditional cash transfer program to alleviate poverty in rural China.Despite the importance of children’s nutrition in breaking poverty cycles,little is known about the impact of Rural Dibao on child nutrition outcomes.Using China Family Panel Studies(CFPS),this paper examines the effects of Rural Dibao on child nutrition outcomes and investigates potential pathways and heterogeneous effects.We exploit propensity score matching and difference-in-differences techniques to evaluate the effects of the Rural Dibao program on child nutrition outcomes.Our results suggest that Rural Dibao significantly impacts the nutrition outcomes of children up to 15 years of age.Specifically,our results suggest that Rural Dibao improves child height-to-age z-scores by 1.05 standard deviations and lowers the probability of stunting by 11.9 percentage points.Additional analyses suggest that increased protein intake is the main pathway through which Rural Dibao participation contributes to better nutrition outcomes.We also find that the effect of the program is more pronounced among girls,children who are non-left-behind or live with highly educated mothers,and those from low-income families and poor areas.Our findings suggest that Rural Dibao participation helps improve child nutrition outcomes through improving diet quality.

Development of a new cerebral ischemia reperfusion model of Mongolian gerbils and standardized evaluation system

Background:The Mongolian gerbil is an excellent laboratory animal for preparing the cerebral ischemia model due to its inherent deficiency in the circle of Willis.However,the low incidence and unpredictability of symptoms are caused by numerous complex variant types of the circle.Additionally,the lack of an evaluation system for the cer-ebral ischemia/reperfusion(I/R)model of gerbils has shackled the application of this model.Methods:We created a symptom-oriented principle and detailed neurobehavioral scoring criteria.At different time points of reperfusion,we analyzed the alteration in locomotion by rotarod test and grip force score,infarct volume by triphenyltetrazo-lium chloride(TTC)staining,neuron loss using Nissl staining,and histological charac-teristics using hematoxylin-eosin(H&E)straining.Results:With a successful model rate of 56%,32 of the 57 gerbils operated by our method harbored typical features of cerebral I/R injury,and the mortality rate in the male gerbils was significantly higher than that in the female gerbils.The suc-cessfully prepared I/R gerbils demonstrated a significant reduction in motility and grip strength at 1 day after reperfusion;formed obvious infarction;exhibited typi-cal pathological features,such as tissue edema,neuronal atrophy and death,and vacuolated structures;and were partially recovered with the extension of reperfu-sion time.Conclusion:This study developed a new method for the unilateral common carotid artery ligation I/R model of gerbil and established a standardized evaluation system for this model,which could provide a new cerebral I/R model of gerbils with more practical applications.

Performance and Safety Improvement of Induction Motors based on Testing and Evaluation Standards

The induction motor,which converts electrical energy into mechanical energy,has been recognized as the cornerstone of industrialization.The rotor of an induction motor can be either a squirrel cage rotor or a wound-type rotor,both existing as magnetless topologies.Three-phase squirrel cage induction motors are frequently utilized in industrial drives because they are dependable,have high starting torque,are selfstarting and affordable.Single-phase induction motors,on the other hand,are commonly used for small loads such as domestic appliances in form of modest fans,pumps and electric power tools.In South Africa,there have been reports of fires and explosions resulting in live and property loss because of induction motors that have not been thoroughly tested or are incorrectly labelled in terms of ratings,electrical safety and performance.The goal of this study is targeted at preventing end-user injuries and failures caused by non-compliant induction motors,by evaluating locally manufactured/imported induction motors based on tests and evaluation from standards(IEC and SANS).The study is conducted using experimental procedures at the Explosion Prevention Technology and Rotating Machines(EPT and RM)laboratory,South African Bureau of Standards(SABS),South Africa.The main finding from the study shows differences in the nameplate characteristics of various induction motors which could have detrimental effects such as production and operational downtime in their end-use industries,at later stages.

Standardized ileal digestibility of amino acids in soybean meal fed to non-pregnant and pregnant sows

Background Two studies were designed to determine standard ileal crude protein(CP)and amino acid(AA)digestibility of soybean meal(SBM)from different origins fed to non-pregnant and pregnant sows.Seven solvent-extracted SBMs from soybeans produced in the USA,Brazil,and China were selected.In Exp.1,eight different diets were created:a nitrogen(N)-free diet and 7 experimental diets containing SBM from different origins as the only N source.Eight non-pregnant,multiparous sows were arranged in an 8×8 Latin square design(8 periods and 8 diets).In Exp.2,the diet formula was the same as in Exp.1.Eight gestating sows(parity 3)were assigned to 4 different diets in a replicated 4×3 Youden square design(three periods and four diets)in mid-gestation and again in late-gestation stages.Results When fed to non-pregnant and late-gestating sows,the standardized ileal digestibility(SID)of CP and most AAs from different SBM were not significantly different(P>0.05).When fed to mid-gestating sows,the SID values for Arg,His,Lys,Phe,Cys,Gly,Ser,and Tyr in SBM 1 were lower than in SBM 4 and 5(P<0.05),whereas SID for Leu from SBM 5 was higher than in SBM 1 and 4(P<0.05).SID values for Ile,Ala,and Asp from SBM 4 were lower than in SBM 1 and 5(P<0.05).Sows had significantly greater SID values for Lys,Ala,and Asp during mid-gestation when compared with late-gestation stages(P<0.05).Mid-gestating sows had greater SID value for Val and lower SID value for Tyr when compared with non-pregnant and late-gestating sows(P<0.01),whereas non-pregnant sows had significantly greater SID value for Met when compared with gestating sows(P<0.01).Conclusions When fed to mid-gestating sows,the SID values for most AAs varied among SBM samples.The SID values for Lys,Met,Val,Ala,Asp,and Tyr in SBM were affected by sow gestation stages.Our findings provide a cornerstone for accurate SBM use in sow diets.

Research on batch multielement rapid quantitative analysis based on the standard curve-assisted calibration-free laserinduced breakdown spectroscopy method

This study proposes a batch rapid quantitative analysis method for multiple elements by combining the advantages of standard curve(SC)and calibration-free laser-induced breakdown spectroscopy(CF-LIBS)technology to achieve synchronous,rapid,and accurate measurement of elements in a large number of samples,namely,SC-assisted CF-LIBS.Al alloy standard samples,divided into calibration and test samples,were applied to validate the proposed method.SC was built based on the characteristic line of Pb and Cr in the calibration sample,and the contents of Pb and Cr in the test sample were calculated with relative errors of 6%and 4%,respectively.SC built using Cr with multiple characteristic lines yielded better calculation results.The relative contents of ten elements in the test sample were calculated using CF-LIBS.Subsequently,the SC-assisted CF-LIBS was executed,with the majority of the calculation relative errors falling within the range of 2%-5%.Finally,the Al and Na contents of the Al alloy were predicted.The results demonstrate that it effectively enables the rapid and accurate quantitative analysis of multiple elements after a single-element SC analysis of the tested samples.Furthermore,this quantitative analysis method was successfully applied to soil and Astragalus samples,realizing an accurate calculation of the contents of multiple elements.Thus,it is important to advance the LIBS quantitative analysis and its related applications.

Combination Activity of Standard Antituberculosis Drugs and Extracts of Medicinal Plants Commonly Used in Traditional Treatment of Tuberculosis in Uganda

Introduction: Resistance to antituberculosis drugs and adverse drug reactions remain the leading causes of tuberculosis therapeutic failure globally. Despite the increasing acceptance of medicinal plant use in combination with conventional antituberculosis drugs in treatment of tuberculosis (TB) in Uganda, there is paucity of knowledge on their combination effect. Aim: This research aimed to determine combination activity of standard antituberculosis drugs with extracts of Zanthoxylum leprieurii Guill. & Perr. and Rubia cordifolia L., the two common antituberculosis medicinal plants in Uganda, against pansensitive (H37Rv) and multi-drug resistant (MDR) Mycobacterium tuberculosis strains. Materials and Methods: Two reference MTB strains (H37Rv and MDR strain) were inoculated on Middlebrook 7H11 medium containing a combination of standard antituberculosis drugs and methanol extracts of Z. leprieurii and R. cordifolia at varying concentrations. The number of colonies on the plates was observed and counted weekly for up to 8 weeks. In vitro combination activity was determined using proportion method. Mean percentage inhibition was calculated for the reduction of number of colonies on drug-extract combination medium in relation to drug-extract-free control medium. Results: Drug-extract combinations showed good combination activity against Mycobacterium tuberculosis strains when compared with individual standard anti-TB drugs. This was more exhibited against MDR strain. There was however a reduction in percentage inhibition when extracts were combined with ethambutol and streptomycin against H37Rv strain. Conclusions: Zanthoxylum leprieurii and Rubia cordifolia in combination with standard anti-TB drugs exhibited increased in vitro activity against Mycobacterium tuberculosis, especially MDR-TB strain. This justifies the local use of these plants in traditional treatment of tuberculosis especially in resistant cases in Uganda.

Standardization of meibomian gland dysfunction in an Egyptian population sample using a non-contact meibography technique

AIM:To develop normative data for meibomian gland dysfunction(MGD)parameters,using non-contact meibography technique of Sirius Costruzione Strumenti Oftalmici(CSO)machine,in an Egyptian population sample.METHODS:Observational,cross-sectional,analytic study,in which 104 Egyptian volunteers were included.Both upper lids were examined,using“Sirius CSO”machine.Each eyelid was given a degree of meibomian gland loss(MGL),which was calculated by the software of the machine.RESULTS:Mean percentage MGL in right upper lid was of 30.9%±12.6%,and that of left upper lid was 32.6%±11.8%.Thirty-four volunteers(32.7%)had first-degree MGL in their right upper lid,and 67.3%had second-degree loss.One volunteer(1%)had zero-degree MGL in left upper lid,28(26.9%)had first-degree loss,and 75(72.1%)had second-degree loss.Degree of MGL in right upper eyelid was not related to age,but degree of MGL in left upper eyelid increased with age.There was statistically significant difference between both genders for degree of MGL in right eye(P=0.036)and in left eye(P=0.027).CONCLUSION:Noncontact meibography is a useful non-invasive tool for diagnosing MGL.MGL is diagnosed in 100%of apparently normal individuals;26.9%-32.7%of which have first-degree MGL,and 67.3%-72.1%have second-degree MGL.

Analysis of standardization development of TCM in Sichuan

Sichuan province is home to rich traditional Chinese medicine(TCM)resources.Recent years have seen unremitting efforts of TCM standardization in the province.By analyzing the measures and existing problems,this paper provides recommendations to boost TCM development through standardization.

PDE Standardization Analysis and Solution of TypicalMechanics Problems

A numerical approach is an effective means of solving boundary value problems(BVPs).This study focuses on physical problems with general partial differential equations(PDEs).It investigates the solution approach through the standard forms of the PDE module in COMSOL.Two typical mechanics problems are exemplified:The deflection of a thin plate,which can be addressed with the dedicated finite element module,and the stress of a pure bending beamthat cannot be tackled.The procedure for the two problems regarding the three standard forms required by the PDE module is detailed.The results were in good agreement with the literature,indicating that the PDE module provides a promising means to solve complex PDEs,especially for those a dedicated finite element module has yet to be developed.

Dialogue on standards:directions and difficulties of standardization discipline construction

To probe into the directions and difficulties of standardization discipline construction in China,China Standardization Press organized a pertinent dialogue on July 10.During the event,Yu Xinli,President of China Association for Standardization,was invited as the moderator.Several standardization experts including Song Mingshun,Mai Lyubo,Qiang Yi,Cao Lili,and Huang Manxue from the China Standardization Expert Committee and renowned universities and research institutes in the country were invited as guests to give their insightful views.

Post competency training in standardized training of resident physicians and integrated postgraduates

We focus on the importance and necessity of post-competency-based training in medical education alongside its current challenges and opportunities.Integrating post competency training into standardized educational frameworks is increasingly recognized as a critical component of preparing residents and postgraduates for real-world clinical practice.Post competency training represents a commitment to excellence in medical education,striving to produce competent,skilled practitioners to meet the challenges of modern healthcare.

Analysis of standardization of community security fund management-Taking practice of community security fund management in Wuhou district of Chengdu as an example

The Chengdu community security funds refer to the special security funds for urban and rural community development and governance in Chengdu.At present,there are some problems in the use of community security funds,such as low participation of residents,and low efficiency of fund use.Taking the exploration of standardization of community security fund management in Wuhou district,Chengdu city,as an example,this paper suggests further strengthening the use and management of community security funds by means of standardization,ensuring the democratic,open,and transparent use of funds,and effectively enhancing the supporting role of community security funds in community governance.

Workshop on driving inclusiveness in standardization

With the support of the Belgian FPS Economy,SBS and CEN-CENELEC are co-organizing the workshop,under the High-Level Forum on European standardization(HLF)and its workstream on inclusiveness in national standardization,to tackle issues of access and participation in standardization at the national level and discuss and promote best practices.

Parallel session on marine standardization

The session on marine standardization was successfully held on May 22.Yu Xinli,President of China Association for Standardization(CAS),was invited to deliver a keynote speech.The highlight of her speech is presented as follows。

China and Sri Lanka sign a MoU on standardization

Witnessed by Chinese Premier Li Qiang and Sri Lanka Prime Minister Dinesh Gunawardena,Luo Wen,Minister of SAMR,and Anura Dissanayake,Secretary to the Prime Minster of Sri Lanka,signed a MoU on the standardization area on March 26.

Review on the Development of Cosmetic Industry from the Perspective of Group Standards

From the perspective of group standards, the dynamics of the cosmetic industry in the past few years were briefly reviewed and analyzed, including the number of group standards published, types of group standards, groups, and geographical distribution of the groups. The large number of participating groups and the wide range of geographical distribution indicated that group standards could play a positive role in the sustained and positive development of cosmetic industry. The future development of cosmetic industry was also prospected。

Field Load Test Based SHM System Safety Standard Determination for Rigid Frame Bridge

The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation process. Thestiffness of the repaired bridge is improved, and the maximum deflection of the load test is reduced from 37.9 to27.6 mm. A bridge health monitoring system is installed after the bridge is reinforced. To achieve an easy assessmentof the bridge’s safety status by directly using transferred data, a real-time safety warning system is createdbased on a five-level safety standard. The threshold for each safety level will be determined by theoretical calculationsand the outcomes of static loading tests. The highest risk threshold will be set at the ultimate limit statevalue. The remaining levels, namely middle risk, low risk, and very low risk, will be determined usingreduction coefficients of 0.95, 0.9, and 0.8, respectively.

Quality Standard of Tibetan Medicine Nardostachys jatamansi Herba Based on"An Integrated Plant but Multi-purpose"

[Objectives]To establish the quality standard of Nardostachys jatamansi Herba.[Methods]The characters and microscopical identification of N.jatamansi Herba were carried out.The contents of moisture,total ash,acid-insoluble ash and extract were determined according to the relevant methods of the Chinese Pharmacopoeia(2020 edition).Using chlorogenic acid and 3,5-O-dicaffeoylquinic acid as quality control indexes,TLC and HPLC methods were established for qualitative and quantitative determination,and HPLC fingerprints were established.[Results]The characteristics of character identification,microscopic identification and thin layer identification were obvious.The moisture content ranged from 2.7%to 7.8%,with an average value of 5.4%.The total ash content ranged from 6.7%to 16.2%,with an average of 11.0%.The acid-insoluble ash content ranged from 0.7%to 8.5%,with an average of 3.6%.Extractives content ranged from 20.9%to 34.4%,with an average of 29.7%.Chlorogenic acid content was between 0.45%and 1.30%,with an average value of 0.77%.The content of 3,5-O-dicaffeoylquinic acid ranged from 0.18%to 0.58%,with an average of 0.31%.The similarity of each batch was between 0.930 and 0.994,indicating that the quality of medicinal materials from different producing areas was stable.[Conclusions]The quality standard of N.jatamansi Herba was established,which could provide quality control basis for rational,comprehensive and efficient utilization of N.jatamansi DC.resources and clinical use.