Numerical and experimental study on the falling film flow characteristics with the effect of co-current gas flow in hydrogen liquefaction process

Liquid hydrogen storage and transportation is an effective method for large-scale transportation and utilization of hydrogen energy. Revealing the flow mechanism of cryogenic working fluid is the key to optimize heat exchanger structure and hydrogen liquefaction process(LH2). The methods of cryogenic visualization experiment, theoretical analysis and numerical simulation are conducted to study the falling film flow characteristics with the effect of co-current gas flow in LH2spiral wound heat exchanger.The results show that the flow rate of mixed refrigerant has a great influence on liquid film spreading process, falling film flow pattern and heat transfer performance. The liquid film of LH2mixed refrigerant with column flow pattern can not uniformly and completely cover the tube wall surface. As liquid flow rate increases, the falling film flow pattern evolves into sheet-column flow and sheet flow, and liquid film completely covers the surface of tube wall. With the increase of shear effect of gas-phase mixed refrigerant in the same direction, the liquid film gradually becomes unstable, and the flow pattern eventually evolves into a mist flow.

Research on the falling film flow and heat transfer characteristics of FLNG spiral wound heat exchanger under sea conditions

As the key equipment of floating liquefied natural gas(FLNG)process,the performance of spiral wound heat exchanger(SWHE)influences operation costs and reliability of the whole system.The sea conditions destroy the falling film flow state of the refrigeration and then affect the heat transfer performance of FLNG SWHE.In order to design and optimize the SWHE,a cryogenic experimental device of FLNG process and a numerical model of falling film flow have been constructed to study the effects of sea conditions on the falling film flow and heat transfer characteristics of SWHE.The cryogenic experimental results show that the pitching conditions have larger effects on the heat transfer performance than yawing.Under the pitching angle of 7°,the natural gas temperature and gaseous refrigerant temperature increase by 3.22°C and 7.42°C,respectively.The flow rates of refrigerant and feed natural gas have a great impact on the heat transfer performance of SWHE under pitching and compound sloshing conditions.When the tilt angle increases to 9°,the tube structure with outer diameter D=8 mm and pipe spacing S=4 mm is recommended to reduce the drying area of the pipe wall surface.

Simulation of the hydrodynamics and mass transfer in a falling film wavy microchannel

The flow in a liquid falling film is predominantly laminar,and the liquid-side mass transfer is limited by molecular diffusion.The effective way to enhance the mass transfer is to improve the liquid film flow behavior.The falling film behaviors of water,ethanol and ethylene glycol in nine different wavy microchannels were simulated by Computational Fluid Dynamics.The simulation results show that the falling film thickness exhibits a waveform distribution resulting in a resonance phenomenon along the wavy microchannel.The fluctuation of liquid film surface increases the gas-liquid interface area,and the internal eddy flow inside the liquid film also improves the turbulence of liquid film,the gas-liquid mass transfer in falling film microchannels is intensified.Compared with flat microchannel,the CO_(2) absorption efficiency in water in the wavy microchannel is improved over 41%.Prediction models of liquid film amplitude and average liquid film thickness were established respectively.

Effects of ABA Content on the Development of Abscission Zone and Berry Falling After Harvesting of Grapes

The commodity price of grape reduces as berry falling after harvest. It is crucial to prevent grape from berry falling during storage. In this article, the structure change of grape cells in the abscission zone was observed, the ABA content and the activities of cellulase and polygalacturonase （PG） were measured, and the relationship of ABA and berry falling was investigated. The results suggest that cells in the abscission zone grow into a separation layer soon after the grapes are cut off. According to the level of development, we designed 6 grades to sort the different development stages. The grade 3 plays an important role in berry falling. ABA enhances the activities of cellulase and polygalacturonase, and accelerates the decomposition of cellulose and pectin, which determines the level of development of abscission zone and berry falling. If ABA ratio is less than 20 ng g-i flesh weight （FW）, the abscission zone is not developed to the grade 3, and the berry falling is effectively stopped. We treated grape bunches with nine plant growth regulators and two chemicals. The results indicated that 2,3,5-triiodobenzoic acid （TIBA） can （a） inhibit the generation of ABA significantly, （b） inactivate the activities of cellulase and PG, （c） delay the development of the grade 3 of abscission zone, and （d） stop berry falling. Indole acetic acid （IAA）, gibberellic acid （GA3）, naphthalene acetic acid （NAA）, 6-benzylaminopurine （6-BA）, calcium chloride （CaCl2）, and potassium permanganate （KMnO4） caused similar results as TIBA. Chlorocholine chloride （CCC）, dimethyl amino succinamic acid （B9）, chloroethylphosphonic acid （CEPA） and exogenous ABA showed opposite effects.

St Lawrence Seaway: Eastern Great Lakes, the Niagara River and Welland Canal Replacement, Maintenance and Protection

The Eastern Great Lakes region covers 51,000 square km of land, and is home to 15 million people. This region is rich in natural resources, industry and agriculture, and forms the heartland of both Canada and the United States. The development of this region has a history that is closely tied to waterways, and the development of canals that promoted growth and prosperity. The St. Lawrence Seaway connects Western and Eastern Great Lakes to the St Lawrence River and the Gulf of Saint Lawrence. The New York State Canal and the St. Lawrence Seaway were linked by the Oswego canal and provided a shorter route for cargo via barges to New York City. The New York State (NYS) Barge Canal and the St. Lawrence Seaway provided pathways for the settlement of the Eastern Great Lakes. Lake Erie drains into Lake Ontario via the Niagara River but the river was not navigable due to the obstacles of Niagara Falls and the Niagara Escarpment. Until the 1820s ships could not travel into Lake Erie. It was not possible to engineer a bypass of Niagara Falls with a series of locks due to the 100 m high Niagara escarpment. This escarpment obstacle to Niagara River navigation was overcome in 1829 with the completion of the first of four Welland Canals with locks 40 kilometers west of the Niagara River through the glacial till and alluvium that overlays the Niagara Escarpment. This permitted ocean going ships to enter Lake Erie and to continue on to Lake Michigan, Lake Huron and Lake Superior. The Eastern Great Lake shorelines, river banks and canals are actively eroding as a consequence of high surface water levels and flooding. The settlement of millions of people into the Eastern Great Lakes via the NYS Barge Canal and St. Lawrence Seaway migration pathways have created environmental and natural resource risks and challenges. These challenges and risks include deterioration of the Fourth Welland Canal and the need to replace it with the Fifth Welland Canal, industrial and urban wastewater disposal, shoreline, river bank and canal erosion as results of high water levels, the building of structures on the shoreline banks, invasive species and flooding.

Influence of Proxies on the Reported Frequency of Falls, Fear of Falling and Activity Restriction in Older People

Introduction: In older populations, the help of a third person may be necessary for a certain number of individuals in order to fill in questionnaires. The influence of this assistance on the collected information can raise questions, among others concerning the concordance between the information provided by the persons themselves and by their proxies, or the introduction of a potential bias. Our study’s objective is to examine, among older people, the differences in the reported frequency of falls, fear of falling and activity restriction due to fear of falling, according to the fact that people had filled in a questionnaire with or without the help of a third person. Methods: The data used come from the secondary analysis of a cross-sectional survey using a self-administered questionnaire and conducted in 2006 in a Belgian semi-rural town among non-institutionalised persons aged 65 years and over. Results: Among the 501 questionnaires, 16.4% were filled in with the help of another person. In bivariate analysis, the persons who needed help reported fall history, fear of falling and activity restriction significantly more often. In multivariable analysis, when considering concurrently the covariates (sex, age, living alone and fall history for fear of falling and for activity restriction), the influence of having received help to fill in the survey was only significant for activity restriction. Conclusion: Our study shows that it is important to know whether or not a person has received help to fill in a questionnaire. This can actually influence the reported frequency of certain outcomes, even, for activity restriction, when considering simultaneously the effect of other covariates. Given the current and future ageing of our populations, it seems that more extensive exploration is needed of the influence of proxies on the collected information about falls, fear of falling and activity restriction among older people.

Physical Activation of Elderly and the Decrease of Falling Risk

A Physical Activation Program was designed and implemented with a particular emphasis in recovering of motor independence, and in an indirect manner;the increase of activities was carried out in a social context in such a way that it allowed isolated elderly to develop their ability to perform daily activities diminishing the burden on their caregivers. 30 people were randomly selected: 15 subjects in the experimental group and 15 in the control group;7 women and 8 men each group. Subjects aged between 60 - 84 years with a mean age of 78 years and a standard deviation of 6.5 were applied in a three-month Physical Activation Program with a 45-min daily sessions. Results obtained showed that physical activity in elderly, systematically improved their amplitude and joint mobility which impact directly and indirectly their quality of life, reducing their risk of falling.

Center of gravity transfer velocity during sit-to-stand is closely related to physical functions regarding fall experience of the elderly living in community dwelling

This study examines the difference of the center of gravity (CG) velocity during sit-to-stand (STS) movement between the elderly with and without fall experience. Fifteen elderly without fall experience (age: 75.7 ± 4.8 yr), with one fall experience (age: 75.7 ± 5.0 yr), and two or more fall experiences (age: 75.7 ± 4.8 yr) participated in the measurement of 10m maximal walking speed, functional reach, one-legged standing duration with vision, maximal isometric knee extension, hip flexion, ankle extension and toe flexion muscle strengths, fall risk assessment and ADL questionnaire, and CG velocity during STS movement. No significant differences were found in muscle strength, walking and balance tests (F 0.078). The group with two or more fall experiences was significantly higher than the other groups in the fall risk assessment, and lower than the group without fall experience in ADL (F = 8.5 and 6.1, p = 0.001 and 0.005). Meanwhile, significant differences were found in the maximal and mean CG velocity during STS movement among all groups. The group without fall experience was the greatest, and the group with fall experience was less than half (F = 9.0 and 11.1, p = 0.001

Developed Numerical Simulation of Falling and Moving Objects in Viscous Fluids under the Action of a Reynolds Lubrication Theory and Low Reynolds Numbers

The development work focuses on the numerical simulations of free body movement in viscous fluid. The aim is to make the simulation of very slow motion of the small body in viscous fluid. We developed bodies’ immersed dynamics simulations in viscous fluid by seeking numerical solutions for appropriate field variables. We developed the methods for vertically and spherically cylindrical objects’ motions, the forces on bodies close to a plane stationary wall are computed from the velocity and pressure fields using the Stokes equation through COMSOL Multiphysics finite element software. The Navier-Stokes equation is reduced to Stokes equation there is independence of time which means object will have an effect only on the motion and the slightly compressible flow assumption is made in order to obtain smooth solution numerically. The forces on an object in slightly compressible Stokes flow have been exerted on the falling objects. The resulting forces have compared with analytical results from the Reynolds Lubrication Theory, and achieved significant results from the development method in Matlab and achieved significant numerical simulations in COMSOL. In addition, an investigation has been made to an object swimming at low Reynolds number. At low Reynolds number moving is possible when object scale is small and flow pattern is slow and sticky. We have developed a system for a thin two-dimensional (2D) worm-like object wiggle that is passing a wave along its centreline and its motion has simulated by the Ordinary Differential Equations (ODE) system and by the Arbitrary Lagrangian-Eulerian (ALE) moving mesh technology. The development method result shows that it is possible for the small object to have a motion from one position to another through small amplitudes and wavelengths in viscous fluid.

Diagnosis of the Physical Area of Community-Dwelling Adults

A situational analysis of aspects related to the physical area of elderly residents of permanent stay of the city of Chihuahua was performed. Participating in the study 51 subjects, 30 women and 21 men, Tinetti and trunk flexion EUROFIT scales were applied to assess fall risk and range of motion. The poor results in balance, gait and range of motion can be stated that most of them are in serious risk of falling. The results obtained show the urgency of starting a physical activation program that emphasizes directly in recovery mobile independence so that enable seniors asylees enhance your ability to perform activities of daily life and reduce the burden on their caregivers.

In Community Dwelling Females Age 65 or Older, Gait Speed Declines as Kinesthetic Awareness of the Lower Legs Decreases

Purpose: This study investigates the existence of a correlation between the gait speed and kinesthetic sense in lower legs and to conduct further analysis of kinesthetic sense in relation to the risk of fall among community dwelling females aged 65 years or older. Materials and Methods: A non-experimental correlational, descriptive, and cohort study included 38 community dwelling females (average age of 82.5 years). The kinesthetic ruler (K-Ruler) and kinesthetic test protocol were created and used to assess lower extremity kinesthetic awareness. The GaitRite System was used to assess gait speed. Each subject was categorized into four groups: “LL” (Low K-Score and low gait speed), “LH” (Low K-Score and high gait speed), “HL” (High K-Score and low gait speed), and “HH” (High K-Score and high gait speed) according to kinesthetic awareness and gait speed measured. Voluntary fall incidence reporting over the 6-month period was followed by the initial data collection. Results: Pearson product-moment correlation (2-tailed) showed that there is a statistically significant, positive moderate-to-strong correlation between K-score and gait speed (ICC = 0.692, p Discussion: Gait speed declines as kinesthetic awareness of lower extremity decreases in community dwelling 65 or older female subjects. Additionally, the combination of kinesthetic awareness and gait speed can be served as a predictor of fall risk. The K-ruler can be used to assess lower extremity kinesthetic awareness in older people as a feasible and standard test.

A New Fractional Model for the Falling Body Problem

Recently, a conformable fractional derivative has been proposed to calculate the derivative of non-integer order of time functions. It has been shown that this new fractional derivative definition obeys many advantages over the preceding definitions. For mathematical models in applied sciences and to preserve the dimensionality of the physical quantities, an auxiliary parameter （~r） which has the dimension of seconds should be implemented in the fractional derivative definition. We obtain analytic solutions for the resulting conformable fractional differential equations describing the vertical velocity and the height of the falling body. It is shown that the dimensions of velocity and height are always correct without any restrictions on the auxiliary parameter cr which contradicts with the results in the literature when applying the Caputo definition to the same problem. This may open the door for many future works either to describe the role of such an auxiliary parameter or to derive a more suitable definition for the fractional derivative.

Observation on the Risk of Falling and Self-efficacy in Elderly Patients with Hip Fracture

Objectives:To study the risk of falling and self-efficacy in elderly patients with hip fracture.Methodology:Forty elderly patients with hip fractures that were caused by falling were admitted into our hospital from April 2018 to April 2019,and were enrolled into this study.All patients were assessed by using the Morse Fall Scale(MFS)and Falls Efficacy Scale(FES).The basic situation of the patients with hip fractures caused by falling and the scores of MFS and FES before and after falling were evaluated.Results:Results showed that the number of patients with femoral neck fractures accounted for 70%out of all patients,and the number of patients with intertrochanteric fractures accounted for the remaining 30%of the patients.The number of patients with academic qualification below primary school is 16,the number of patients with middle high school education is 11 and the number of patients with high school education and above is 13.Slipping is the cause of hip fracture that accounted for the most in patients,followed by outing activities,whereas least patients with hip fractures was caused by falling in nursing home.There were 29 patients’who used crutches or walking aids and this number was more than that of those who required the devices.After the MFS and FES analyses,the results(scores of MFS and FES)showed that the risk before the fall was lower.In contrast,the risk of fracture and post-surgery after the fall was greatly increased.Conclusion:The elderly patients with hip fractures were found to have increased risk of falling and thus,these patients require good care.

Fall Prevention Education Reduces the Falling Rate on the Osteoporosis Patients Treated with Zoledronic Acid

Objective: Falls are one of the most common direct causes of fractures which are major causes of morbidity and mortality in osteoporosis patient. There are many factors related to falls, by interfering of fall prevention education on the patients with osteoporosis, our study is to investigate whether fall prevention education can reduce the falling rate on the osteoporosis patients treated with zoledronic acid. Methods: A total of 178 eligible female patients who first visited our osteoporosis department during January 2016 to June 2017 were invited to participate in this study, and all participants were randomly divided into an observation group (92 cases) and an intervention group (86 cases). All patients were administrated zoledronic acid once and received a questionnaire survey about factors related to falls at the beginning and a year later. The patients in the observation group only received regular orders of adopting a healthy lifestyle while those in the intervention group received fall prevention assessment and education, and a telephone follow-up and reinforced fall prevention education a month after discharge. A year later, relevant data regarding the falls of each patient of both groups during the year and the data of the questionnaire survey were collected for intergroup comparison. Results: The difference of the improvement of fall risk factors between the two groups is statistically significant (P Conclusion: For an osteoporosis patient treated with zoledronic acid, fall prevention education is an effective method to reduce the risk of falling, which would result in a lower risk of fractures and a better prognosis.

＂Falling Oil Prices＂ and ＂Crisis Awareness＂： Oil＇s Continued Reign as the World＇s Biggest Energy Source

On July 5, 2017, BP released the BP Statistical Review of World Energy（2017） in Beijing, which reviews and analyzes the production and consumption of various types of energy in the world for the past year. Spencer Dale, BP＇s chief economist, detailed global energy production and demand in 2006. He reported a piece of＂big＂ news： the proportion of oil in the world＇s primary energy consumption didn＇t decrease in 2016, but rather increased by 0.15% from 2015 to 33.27% （33.12% in 2015）,

The Contribution of Health Education to the Falling Incidence within Hospital Premises in China

Falling is the second leading cause of accidental injury to death worldwide.It is estimated that more than 80%of the people die each year in low and middle-income countries.Falling is also the leading cause of death among the elderly in China.Among them,the falling rate in 2016 increased by 5%compared with 2006.Although not fatal,those who fell and have a disability,which may face significant economic risks associated with subsequent long-term care needs,especially for the elderly[凹].It may be essential to use evidence-based guidelines for proving health education to address the issue of preventing hospitalization for the elderly.This article will combine the author's practical experience to examine the contribution of health education to prevent falls and explore its application and development in China.Lastly,it will explain barriers to health education.

Factors associated with the incidence of patient falls in hospitals:A scoping review

When a patient falls within a hospital setting,there is a significant increase in the risk of severe injury or health complications.Recognizing factors associated with such falls is crucial to mitigate their impact on patient safety.This review seeks to analyze the factors contributing to patient falls in hospitals.The main goal is to enhance our understanding of the reasons behind these falls,enabling hospitals to devise more effective prevention strategies.This study reviewed literature published from 2013 to 2022,using the Arksey and O’Malley methodology for a scoping review.The research literature was searched from seven databases,namely,PubMed,ScienceDirect,Wiley Library,Garuda,Global Index Medicus,Emerald Insight,and Google Scholar.The inclusion criteria comprised both qualitative and quantitative primary and secondary data studies centered on hospitalized patients.Out of the 893 studies analyzed,23 met the criteria and were included in this review.Although there is not an abundance of relevant literature,this review identified several factors associated with falls in hospitals.These encompass environmental,patient,staff,and medical factors.This study offers valuable insights for hospitals and medical personnel aiming to enhance fall prevention practices.Effective prevention efforts should prioritize early identification of patient risk factors,enhancement of the care environment,thorough training for care staff,and vigilant supervision of high-risk patients.By comprehending the factors that contribute to patient falls,hospitals can bolster patient safety and mitigate the adverse effects of falls within the health-care setting.

Analysis of the Clinical Interventions for Falls in Elderly Patients in the Community From 2002 To 2022:A Bibliometric Analysis

Objective:To analyze and provide a comprehensive overview of the knowledge structure and research hotspots of clinical interventions for falls in elderly patients in the community.Methods:The search for publications related to clinical interventions for falls in elderly patients in the community from 2002 to 2022 was conducted on the Web of Science Core Collection(WoSCC)database.VOSviewers,CiteSpace,and the R package“bibliometrix”were used to conduct this bibliometric analysis.Results:2091 articles from 70 countries,primarily the United States and Australia,were included.The number of publications related to clinical interventions for falls in elderly patients is increasing yearly.The main research institutions in this field were the University of Sydney,Harvard University,and the University of California.BioMed Central(BMC)Geriatrics was the most popular journal in this field and Journals of the American Geriatrics Society was the most co-cited journal.These publications came from 8984 authors among which author Lord SR had published the most papers and author Tinetti Me had the most co-citations.The main keywords in this research field were“balance,”“exercise,”and“risk factor.”Conclusion:This was the first bibliometric study that comprehensively summarized the research hot spots and development of clinical interventions for falls in elderly patients in the community.This paper aims to provide a reference for scholars and researchers in this particular field.

Biomass, litterfall and the nutrient fluxes in Chinese fir stands of different age in subtropical China

Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.), a fast-growing, ever-green conifer tree with high yield and excellent quality, is the most important tree species of timber plantations in subtropical China. We investigated the characteristics of biomass, litterfall and nutrient fluxes in the 8, 14 and 24 year-old stands, representing the young, middle-aged and mature stands. The results showed that Chinese fir plantations in central Fujian province had high productivity, and the proportion of stem mass in total biomass was between 50%-70%. Chinese fir was low nutrient-return tree species with litterfall. Nutrient withdrawal from senescing needles was a strong age-dependence for nitrogen, phosphorous and potassium in Chinese fir. With a management system of such short-rotation and continuously pure-crop planting, harvesting timber can lead to great nutrient loss, which may be one of the causes for site degradation.