THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

The Design and Analysis of Experiments

BACKGROUND Synthetic membranes are used for desalination, dialysis, sterile filtration, food processing, dehydration of air and other industrial, medical, and environmental applications due to low energy requirements, compact design, and mechanical simplicity. New applications are emerging from the water-energy nexus, shale gas extraction, and environmental needs such as carbon capture. All membranes exhibit a trade-off between permeability—i.e., how fast molecules pass through a membrane material—and selectivity—i.e., to what extent the desired molecules are separated from the rest. However, biological membranes such as aquaporins and ion channels are both highly permeable and highly selective. Separation based on size difference is common, but there are other ways to either block one component or enhance transport of another through a membrane. Based on increasing molecular understanding of both biological and synthetic membranes, key design criteria for new membranes have emerged: (i) properly sized free-volume elements (or pores), (ii) narrow free-volume element (or pore size) distribution, (iii) a thin active layer, and (iv) highly tuned interactions between permeants of interest and the membrane. Here, we discuss the permeability/selectivity trade-off, highlight similarities and differences between synthetic and biological membranes, describe challenges for existing membranes, and identify fruitful areas of future research. ADVANCES Many organic, inorganic, and hybrid materials have emerged as potential membranes. In addition to polymers, used for most membranes today, materials such as carbon molecular sieves, ceramics, zeolites, various nanomaterials (e.g., graphene, graphene oxide, and metal organic frameworks), and their mixtures with polymers have been explored. Simultaneously, global challenges such as climate change and rapid population growth stimulate the search for efficient water purification and energy-generation technologies, many of which are membrane-based. Additional driving forces include wastewater reuse from shale gas extraction and improvement of chemical and petrochemical separation processes by increasing the use of light hydrocarbons for chemicals manufacturing. OUTLOOK Opportunities for advancing membranes include (i) more mechanically, chemically, and thermally robust materials; (ii) judiciously higher permeability and selectivity for applications where such improvements matter; and (iii) more emphasis on fundamental structure/property/processing relations. There is a pressing need for membranes with improved selectivity, rather than membranes with improved permeability, especially for water purification. Modeling at all length scales is needed to develop a coherent molecular understanding of membrane properties, provide insight for future materials design, and clarify the fundamental basis for trade-off behavior. Basic molecular-level understanding of thermodynamic and diffusion properties of water and ions in charged membranes for desalination and energy applications such as fuel cells is largely incomplete. Fundamental understanding of membrane structure optimization to control transport of minor species (e.g., trace-organic contaminants in desalination membranes, neutral compounds in charged membranes, and heavy hydrocarbons in membranes for natural gas separation) is needed. Laboratory evaluation of membranes is often conducted with highly idealized mixtures, so separation performance in real applications with complex mixtures is poorly understood. Lack of systematic understanding of methodologies to scale promising membranes from the few square centimeters needed for laboratory studies to the thousands of square meters needed for large applications stymies membrane deployment. Nevertheless, opportunities for membranes in both existing and emerging applications, together with an expanding set of membrane materials, hold great promise for membranes to effectively address separations needs.

http://science.sciencemag.org/content/sci/356/6343/eaab0530.full.pdf

Maximizing the right stuff: The trade-off between membrane permeability and selectivity

In this article, several applications of nanomaterials in food packaging and food safety are reviewed, including: polymer/clay nanocomposites as high barrier packaging materials, silver nanoparticles as potent antimicrobial agents, and nanosensors and nanomaterial-based assays for the detection of food-relevant analytes (gasses, small organic molecules and food-borne pathogens). In addition to covering the technical aspects of these topics, the current commercial status and understanding of health implications of these technologies are also discussed. These applications were chosen because they do not involve direct addition of nanoparticles to consumed foods, and thus are more likely to be marketed to the public in the short term.

Applications of nanotechnology in food packaging and food safety: Barrier materials, antimicrobials and sensors

Energy-efficient polymeric gas separation membranes for a sustainable future: A review

The membrane gas separation industry is 35 years old and growing at a significant rate. Development of higher selectivity and higher permeance membranes would result in faster growth. This paper will analyze the barriers that have inhibited the development of these membranes. We start by reviewing the lessons that can be drawn from the past 35 years of experience. We then review the needs and most promising research directions for new materials in current and future membrane applications.

Gas Separation Membrane Materials: A Perspective

Gas-liquid direct-contact evaporators are characterized by the bubbling of a superheated gas through the solution to be concentrated. In other words, they are nonisothermal bubble columns. Despite their simplicity of construction, these units exhibit rather complex hydrodynamics and, similar to what occurs to isothermal bubble columns, the design of such units still poses a problem. The present paper reviews the literature regarding this kind of equipment, addressing both experimental studies and modeling efforts. The covered issues include classic and potential applications, bubbling regimes, gas holdup and bubble size distributions, as well as mathematical models proposed for simulating the unit. Additionally, pertinent literature on isothermal bubble columns is also discussed. Recommendations are made for future research.

Gas‐Liquid Direct‐Contact Evaporation: A Review

Innovative Techniques Opportunities and Challenges in Nonthermal Processing of Foods, N.K. Rastogi Trends in Breadmaking: Low and Subzero, C.M. Rosell Biotechnological Tools to Produce Natural Flavors and Methods to Authenticate Their Origin, E. Brenna, G. Fronza, C. Fuganti, F.G. Gatti, and S. Serra Application of Solid-State Fermentation to Food Industry, M.A. Longo and M.A. Sanroman Membrane Processing for the Recovery of Bioactive Compounds in Agro-Industries, S. Velizarov and J.G. Crespo Recent Advances in Fruit-Juice Concentration Technology, C.P. Ribeiro Jr., P.L.C. Lage, and C. P. Borges Encapsulation Technologies for Modifying Food Performance, M. Ines Re, M.H.A. Santana, and M.A. d'Avila Perspectives of Fluidized Bed Coating in the Food Industry, F. Depypere, J.G. Pieters, and K. Dewettinck Spray Drying and Its Application in Food Processing, H.L. Xin and A.S. Mujumdar Superheated-Steam Drying Applied in Food Engineering, S. Prachayawarakorn and S. Soponronnarit Drying of Tropical Fruit Pulps: An Alternative Spouted-Bed Process, M. de Fatima Medeiros, J.S. Souza, O.L.S. Alsina, and S.C.S. Rocha Application of Hybrid Technology Using Microwaves for Drying and Extraction, U.S. Shivhare, V. Orsat, and G.S. Vijaya Raghavan Vacuum Frying Technology, L.P. Fan, M. Zhang, and A.S. Mujumdar Aseptic Packaging of Food-Basic Principles and New Developments Concerning Decontamination Methods for Packaging Materials, P. Muranyi, J. Wunderlich, and O. Franken Controlled and Modified Atmosphere Packaging of Food Products, D. O'Beirne Latest Developments and Future Trends in Food Packaging and Biopackaging, J.M. Lagaron and A. Lopez-Rubio New Materials, Products, and Additives Biodegradable Films Based on Biopolymers for Food Industries, A.C. de Souza, C. Ditchfield, and C.C. Tadini Goat Milk Powder Production in Small Agro-Cooperatives, U.K.L. Medeiros, M. de Fatima Medeiros, and M.L. Passos Meat Products as Functional Foods, J. Fernandez Lopez and J.A. Perez Alvarez Probiotics and Prebiotics in Fermented Dairy Products, G. Vinderola, C. Gonzalez de los Reyes-Gavilan, and J. Reinheimer Uses of Whole Cereals and Cereal Components for the Development of Functional Foods, D. Charalampopoulos, S.S. Pandiella, and C. Webb Advances in Development of Fat Replacers and Low-Fat Products, J.R. Daniel Biosurfactants as Emerging Additives in Food Processing, D.M. Guimaraes Freire, L. Vieira de Araujo, F. de Araujo Kronemberger, and M. Nitschke Index

Innovation In Food Engineering: New Techniques And Products

On the effect of liquid temperature upon bubble coalescence

Pure- and mixed-gas carbon dioxide/ethane permeability and diffusivity in a cross-linked poly(ethylene oxide) copolymer

The hydrodynamics of a rotating disc contactor (76.2 mm diameter, 19 stages, and operating height of 815 mm) has been investigated at limiting operational conditions of low holdup (φ ≤ 3%) and low agitation (Re R  ≤ 22,000) for the water/n-heptane system in the absence of mass transfer. Water was chosen as the continuous phase, and it was kept stagnant inside the column. Local drop size distribution, local mean drop diameter, and total holdup have been measured at different flow rates of the dispersed phase (70 to 640 mL/min) and rotor speeds (0 to 700 rpm). Drop size distributions along the column were suitably described using the log-normal probability density function, and empirical expressions were derived to predict the parameters of the distribution curve as a function of operating conditions. An empirical expression was also proposed to predict the Sauter mean drop diameter along the column with a mean deviation of 3.4%. Statistical analysis has revealed no significant effect of the rotor ...

Cláudio P. Ribeiro

Papers

Gas‐Liquid Direct‐Contact Evaporation: A Review

Innovation In Food Engineering: New Techniques And Products

On the effect of liquid temperature upon bubble coalescence

Pure- and mixed-gas carbon dioxide/ethane permeability and diffusivity in a cross-linked poly(ethylene oxide) copolymer

Hydrodynamic Behavior of a Rotating Disc Contactor Under Low Agitation Conditions