Van Olphen Research Articles

Abstract B05: Technical assistance as part of capacity building for collaborative research in breast cancer, the environment, and/or disparities.

Abstract Training and technical assistance efforts for community based participatory research (CBPR) partnerships have the potential to improve outcomes in both scientific rigor and collaboration. Successful competition for regional or national funding for CBPR represents a critical step in this trajectory. To this end, a collaboration funded through this NIEHS award has developed and implemented an intensive training program (Community Based Research Infrastructure to Better Science [CRIBS]) to build capacity among community-academic teams to conduct CBPR into disparities in breast cancer and/or environmental causes of breast cancer. The program includes face-to-face training; online training; mock grant review; and technical assistance (TA); and skill-building in creating CBPR partnerships; understanding the science of the environmental causes of and disparities in breast cancer; creating a pathway from vision to project; and writing successful grant applications. Participants in the training included 31 individuals in 12 partnerships with at least one community and one academic member in each. Fifty-five percent of participants identified as belonging to an ethnic or racial minority group; 81% identified as female; 58% identified as community partners; the mean age was 49.76 years old (median = 52; range = 23 to 71). Partnerships came from twelve locations across California. TA efforts began in the second month of F2F trainings and included: a) four, monthly, tailored, in-person consultations of up to 1.5 hrs in length; b) review of an 8-page concept paper prepared by each team; c) four, monthly, tailored one-hour phone consultations. TA was provided by CRIBS staff and representatives from national funding organizations with expertise in scientific and collaborative aspects of breast cancer research, as well as by experts in the field of CBPR, disparities, and the environment. Over time, improved clarity and specificity were evident in the research questions formulated across partnerships. Implications of tailored, technical assistance for partnerships embarking on CBPR in disparities are discussed. Citation Format: Senaida Fernandez, Marj Plumb, Catherine Thomsen, Braun Susan, Heather Sarantis, Juliana van Olphen, Emily Galpern, Marion Kavanaugh-Lynch. Technical assistance as part of capacity building for collaborative research in breast cancer, the environment, and/or disparities. [abstract]. In: Proceedings of the Fifth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2012 Oct 27-30; San Diego, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2012;21(10 Suppl):Abstract nr B05.

Breast Cancer Environment Centers and Advocacy

As Breast Cancer and Environment Research Center (BCERC) project leaders, we would like to address what we believe represents inaccuracies and omissions in the recent article by Baralt and McCormick (2010). Using self-citations, the authors asserted that genes and environment were not included in breast cancer research before advocacy efforts emerged. Yet the environment has long been implicated in breast cancer etiology; for example, for > 50 years the laboratory model of mammary carcinogenesis has involved administration of environmental chemicals (Medina 2007). Further, the Long Island Breast Cancer Study Project (LIBCSP) was not the first environment–breast cancer grant, as suggested by Baralt and McCormick. The National Institute of Environmental Health Sciences issued such grants as early as 1991, including “Environmental Factors and Breast Cancer in High-Risk Areas” [Request for Applications (RFA) CA/ES-93-024] in 1993. The LIBCSP has been enormously productive, continuing even now, with > 100 scientific publications and $21 million in grant funding using LIBCSP resources. Baralt and McCormick’s (2010) criticism of the LIBCSP ignores the rigorous review process of National Institutes of Health grants, requiring an undeniable hypothesis, scientific plausibility, and high probability of success. What Baralt and McCormick described is the dissatisfaction of some (but not all) advocates with that research process during the initial years of the LIBCSP. Baralt and McCormick (2010) used the word “frustration” 16 times, without noting the impressive contributions of the BCERC Community Outreach and Translation Cores (COTC) projects. Advocacy and COTC in the BCERC since 2003 have resulted in extensive and innovative dissemination of knowledge and new ideas (Breast Cancer and the Environment Research Program 2011). Mutual learning was facilitated by the participation of advocates and research staff in weekly staff meetings, monthly epidemiology and COTC calls, 16 subcommittee meetings and calls, and organizing calls for the biannual meetings. Coordinated COTC, advocate, and scientific sessions were part of the biannual BCERC meetings. Rather than “frustration,” the past 7 years could be better summarized as an ongoing, interactive, collaborative, critical process of science and advocacy–indeed a new paradigm of scientific method. As noted by Baralt and McCormick (2010), the 2002 RFA for BCERC did not require adherence to principles of community-based participatory research. The BCERC COTC members represented a range of experience in community-based participatory research; few had training in basic science. Each center developed different COTC models of community involvement and engagement, not included by Baralt and McCormick in their article. The Bay Area COTC incorporated the principles of community-based, participatory research and used those principles to evaluate the extent to which the approach was participatory and to ascertain the benefits and challenges of the participatory aspects of the project as perceived variously by community, advocacy, and scientific partners (Van Olphen et al. 2009). Other centers used quite different models of community engagement and, accordingly, should be evaluated in a different fashion. Thus, it would have been appropriate for Baralt and McCormick (2010) to assess which model most effectively met the aims stated in the 2002 RFA. Another difference between centers was that, except for the Bay Area, the COTCs were part of a research or academic institution. Thus, we faced multiple challenges on how to effectively involve communities and advocates in research. Over the first 7 years, centers developed a continuum of strategies to create partnerships with the basic scientists and epidemiologists involved in BCERC. Baralt and McCormick (2010) omitted important details describing their methodology from the article. Specifically, in their Table 1 they included demographics about the sex and race/ethnicity of the investigators from BCERC centers, but no similar table characterized the participants in their study. [The Bay Area BCERC COTC included an African-American member, not four whites as Baralt and McCormick showed in their Table 1.] In addition, the authors did not discuss the involvement of advocates compared with nonadvocates in activities of COTCs at the four centers. It was unclear whether survey participants included only scientists and advocates formally connected with the centers (e.g., those listed in their Table 1) or if they included non-BCERC scientists and advocates who attended the conferences. Also, if the respondents in 2005 and 2007 were completely different, as suggested, it was not appropriate to pool the data nor to report any changes over time. We support advocate participation in research, and we recognize that methods for quantifying their contributions require unique approaches.

NIEHS Supports Partnerships in Environmental Public Health

NIEHS Supports Partnerships in Environmental Public Health Linda S. Birnbaum, PhD I would like to start by thanking the journal for inviting me to write an editorial to accompany Dr. Juliana van Olphen and her colleagues’ thoughtful evaluation that focuses on the important topic of community health partnerships.1 As the new director of the National Institute of Environmental Health Sciences (NIEHS) and the National Toxicology Program, I am pleased to take on this role during a time when both the environment and health are top priorities for our country. I am a big supporter of community-based participatory research (CBPR) that ensures community members have an active role in planning, implementing, translating and disseminating research that addresses local environmental health concerns. NIEHS has been a long-standing leader in fostering partnerships between community groups and researchers to better understand environmental causes of disease. Our commitment is demonstrated in a number of ways. For example, NIEHS, in cooperation with the National Cancer Institute, requires that a Community Outreach and Translation Core (COTC) is established in each of our four Breast Cancer and the Environment Research Centers—one of which was the subject of Dr. van Olphen’s independent analysis published in this issue. COTCs conduct essential work to ensure that the views and concerns of the breast cancer advocacy community are heard and that the research findings are disseminated to the public. Developing educational materials for children and adults about breast cancer and the environment, holding public awareness forums and town meetings, and exploring areas of concern or interest to the community are all essential activities led by the COTC to create community participation in environmental health issues such as breast cancer. What van Olphen’s article demonstrates is that COTCs can further advance and promote CBPR principles within research-intensive Centers. NIEHS grantees employing CBPR approaches are contributing to our understanding about breast cancer and the environment. There is a growing body of literature showing that early-life exposures to endocrine disruptors—particularly during gestation and childhood, but also continuing through puberty, first childbirth, and breastfeeding—are critical to later-life breast cancer risk. As researchers learn more about what causes and how to prevent breast cancer, grantees such as those we support through our environmental justice program are spreading the word and empowering communities to take action. Breast cancer advocates in two communities that differ in racial/ethnic and economic character are working in partnership with researchers to assess household exposures to endocrine disrupting compounds, and to develop communication tools for reporting results to affected individuals and communities.2 These research findings are being used by community groups and advocates to affect public health and lead to policy changes. Congress recently recognized the contributions of NIEHS and the National Institutes of Health as a whole for their outstanding work in the breast cancer and environment area, when it passed the “Breast Cancer and Environment Research Act of 2008.”3 The Act looks to NIH to take a lead role in defining the future research agenda for collaborative research efforts related to breast cancer and the environment. NIEHS’ leadership role in translating research on breast cancer and the environment is the outgrowth of the Institute’s commitment to CBPR approaches that promote having the community actively involved in shaping and conducting research and intervention strategies. Since 1995, through its CBPR activities, the Institute has supported principles that have been developed and shared by leaders in the field such as those developed by Barbara Israel et al. 4 and Lawrence Green et al.5 Principles that call for building on the strengths and resources within the community; focusing on the local relevance of public health problems; and disseminating results to all partners are endorsed by NIEHS and are evident in work supported by NIEHS. Recognizing the [End Page 195] continuum of CBPR, the Institute promotes these principles throughout a variety of programs from traditional outreach and education efforts to more complex biomedical, hypothesis-driven research questions that address environmental justice and health disparities issues. To build upon our past accomplishments and to progress our research agenda in this area, we recently sought input from research grantees and members of advocacy...

Baseline Studies of the Clay Minerals Society Source Clays: Preface

The Source Clays Program of The Clay Minerals Society was initiated in 1972 to distribute a set of reference clays, so that distributed clays could be identical for all recipients. Because most clays do not consist of a single phase, the immediate objective was not to produce a pure product consisting of one clay mineral, but to provide a uniform product. These materials were collected and processed carefully, and sufficient amounts were collected so that material was available for researchers for many years, Large numbers of researchers were thereby assured of working on identical material. Initial descriptions of these materials were presented in the Data Handbook (van Olphen and Fripiat, 1979). An updated version of this book was suggested several years ago because of the availability of new analytical techniques and to provide descriptions of material added to the reference set since 1979.

FLOCCULATION OF HOMOIONIC SODIUM PALYGORSKITE, PALYGORSKITE-MONTMORILLONITE MIXTURES AND PALYGORSKITE CONTAINING SOIL CLAYS

Flocculation of palygorskite has not been studied in detail. We have investigated flocculation of reference palygorskites, palygorskite-montmorillonite mixtures, and palygorskite containing soil clays. The flocculation values (FVs) of the clays were measured in a series of test tubes according to van Olphen (1977). The flocculation of the clays was determined visually by settling after 24 h of standing. Very dilute clay suspensions (0.066%) were taken for the tests. The FV of palygorskite at near neutral pH was significantly lower than that of montmorillonite. The FVs of four Na-palygorskites were in the range from 0.2 to 2.5 meq/L NaCl and the FV of Na-montmorillonite from Wyoming was 13.3 meq/L NaCl at pH ∼ 7. FVs of both palygorskite and montmorillonite increased with pH. The effect of pH on FV of palygorskite was more significant than that of montmorillonite. At pH ∼ 10.5, the FVs of all palygorskite samples were 25.0 meq/L NaCl, and the FV of the montmorillonite sample was 50.0 meq/L NaCl. Settling of clay particles was affected by concentration of clay in suspension. Settling was clearly observed in test tubes at a clay concentration of 0.066%. At a clay concentration of 0.666%, however, settling was not observed. The apparent contradiction between low FVs of palygorskite suspensions, obtained in the present study, and low rheological susceptibility of palygorskite muds to salts, known from industrial experience, can be explained by differences in clay concentration used for FV measurements and for industrial applications. FVs of palygorskite-montmorillonite mixtures at pH ∼ 7 increase with montmorillonite percentage in the mixture. At a specific concentration of montmorillonite in the mixture, the FV of the system attains the FV of pure montmorillonite and does not change with further montmorillonite addition. This montmorillonite concentration varied among the palygorskite samples and was in the range of 40 to 60%. FVs of three smectite- palygorskite- kaolinite-containing soil clays (from which carbonates, iron oxides and organic matter had been removed) at near neutral pH values were the same as FV of reference montmorillonite.

Speech recognition in adults with both a cochlear implant and a hearing aid, compared to speech recognition with an implant and no hearing aid

Clinical Otolaryngology & Allied SciencesVolume 24, Issue 4 p. 377-383 Speech recognition in adults with both a cochlear implant and a hearing aid, compared to speech recognition with an implant and no hearing aid M. C. Langereis, M. C. LangereisSearch for more papers by this authorJ. E. Van Dijk, J. E. Van DijkSearch for more papers by this authorA. F. Van Olphen, A. F. Van OlphenSearch for more papers by this authorG. F. Smoorenburg, G. F. SmoorenburgSearch for more papers by this author M. C. Langereis, M. C. LangereisSearch for more papers by this authorJ. E. Van Dijk, J. E. Van DijkSearch for more papers by this authorA. F. Van Olphen, A. F. Van OlphenSearch for more papers by this authorG. F. Smoorenburg, G. F. SmoorenburgSearch for more papers by this author First published: 25 December 2001 https://doi.org/10.1046/j.1365-2273.1999.00280-19.xRead the full textAbout ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume24, Issue4August 1999Pages 377-383 RelatedInformation

The rheological and colloidal properties of bentonite dispersions in the presence of organic compounds; I, Flow behaviour of sodium-bentonite in water-alcohol

Addition of methanol, ethanol, and n-propanol to aqueous dispersions of Namontmorillonite (2% w/w) reduces the apparent viscosity and the yield value. In the presence of NaCl the flow parameters increase to a maximum at medium alcohol concentration. Thus, the gel strength of Nabentonite dispersions can greatly change with the alcohol content of the dispersion. This is probably caused by the transition of dispersed clay mineral particles (individual silicate layers or lamellae of a few of these layers) to band-type networks with optical homogeneity and weakly attractive particle-particle interaction. When attraction between the particles becomes too strong at high alcohol concentrations, the bands are condensed to short fragments and, eventually, freely moving particles, reducing the viscosity and the yield value. The interparticle interaction energy is calculated for the constant charge model by van Olphen's (1977) method. Agreement with the experimental results is only obtained when the Stern layer adsorption is governed by a specific adsorption energy μ, which increases with decreasing dielectric constant.

A portable rotational viscometer for field and laboratory analysis of cohesive sediment suspensions: Faas, R.W., 1990. J. coast. Res., 6(3):735–738

In studies of the erosion, transport, and deposition of dense near bottom suspensions of fine- grained cohesive sediment, it is often useful to ascertain the particular form of rheological behavior which may be exhibited by the suspension as it responds to the stresses imposed upon it by its environment. These forms of behavior may be time-dependent or independent, Newtonian or non- Newtonian and may show some or all forms of rheological behavior during an analysis, depending upon Environmental condition. For a treatment of suspension rheology, see VAN WAZER et al., (1963) and VAN OLPHEN, (1977). The purpose of this note is to describe in some detail an instrument which has been used to make observations of these phenomena, to discuss its usefulness for laboratory and field analyses, and to suggest that it be considered an important tool for understanding and predicting the dynamic behavior of such material.

Book reviews

Gravel‐Bed Rivers, Fluvial Processes, Engineering and Management, ed. by R.D. Hey, J. C. Bathurst and C. R. ThorneInternational Clay Conference 1981, ed. by H. Van Olphen and F. VenialeGeology of Offshore Ireland and West Britain, by D. Naylor and P. M. Shannon.Facies Interpretation and the Stratigraphic Record, by A. Hallam. W. H. FreemanDiagenesis in Sediments and Sedimentary Rocks, ed. by G . Larsen and C. V. ChilingarBasic Well Log Analysis for Geologists, by George Asquith with Charles Gibson.

International Clay Conference, 1981: Proceedings of the VII International Clay Conference held in Bologna and Pavia, Italy, September 6-12, 1981, edited by H. van Olphen and F. Veniale. Developments in Sedimentology 35, Elsevier Scientific Publishing Company, Amsterdam, New York, 1982. xxiv + 828 pages. $93.00, Dfi. 200.00.

<b>International Clay Conference, 1981</b>: Proceedings of the VII International Clay Conference held in Bologna and Pavia, Italy, September 6-12, 1981, edited by H. van Olphen and F. Veniale. Developments in Sedimentology 35, Elsevier Scientific Publishing Company, Amsterdam, New York, 1982. xxiv + 828 pages. $93.00, Dfi. 200.00.

An Introduction to Clay Colloid Chemistry, Second Edition, by H. Van Olphen, John Wiley &amp; Sons, New York, London, Sydney, Toronto, 1977. 318 pp. 39 figures, graphs and tables. Cloth $21.50.

<b>An Introduction to Clay Colloid Chemistry</b>, Second Edition, by H. Van Olphen, John Wiley &amp; Sons, New York, London, Sydney, Toronto, 1977. 318 pp. 39 figures, graphs and tables. Cloth $21.50.

Colloid and surface chemistry, physical chemistry: Enriching topics from colloid and surface science IUPAC Commission 1.6. Edited by H. van Olphen and Karol J. Mysels, Theorex, La Jolla, Calif., 1975, xvi + 404 pages, $6.50

Colloid and surface chemistry, physical chemistry: Enriching topics from colloid and surface science IUPAC Commission 1.6. Edited by H. van Olphen and Karol J. Mysels, Theorex, La Jolla, Calif., 1975, xvi + 404 pages, $6.50

X‐Ray and Electron Methods of Analysis. Progress in Analytical Chemistry, Volume 1. Edited by H. van Olphen and W. Parrish. Plenum Press, New York, 1968. 164 pp. $12.50

X‐Ray and Electron Methods of Analysis. Progress in Analytical Chemistry, Volume 1. Edited by H. van Olphen and W. Parrish. Plenum Press, New York, 1968. 164 pp. $12.50

Crystallochemistry of clay minerals and their properties

Experimental studies on a series of three-layer minerals (pyrophyllite, montmorillonite, hydromica, biotite) have shown the dependence of intercrystalline swelling in these minerals on the degree and localization of isomorphic substitutions in the crystals. With the increase of the magnitude of isomorphic substitutions, the degree of intercrystalline swelling will at first rise and then decline. It has also been shown that the increase of isomorphic substitutions in the tetrahedral layer raises the non-exchangeable K+ ion content in these minerals and lowers their swelling capacity. Measurements of clay particle orientation in electrostatic field at different pH values of the medium indicate that the edges of clay mineral crystals have a positive charge in the acid medium and a negative charge in the alkaline medium, which confirms the views previously expressed by Van Olphen, Schofield and Samson. The data obtained suggest that in the acid medium the basal surfaces and the edges of clay mineral particles have an opposite double electric layer. These observations make it possible to explain a number of structural-mechanical features of clays and thus to get a more comprehensive understanding of the nature of their strength.

Equivalent Pasteurization Temperatures to Kill Salmonellae in Liquid Egg White at Various pH Levels

THE pH of the medium has a major influence on the susceptibility of bacteria to heat. Hansen and Riemann (1963), in a review of factors affecting the heat resistance of nonsporing organisms, indicated that maximum resistance usually occurs near neutrality. Most pasteurization studies either have not considered or have given little attention to pH as a variable in altering the time and/or temperature required to kill bacteria in liquid egg white (EW).A review of the literature revealed the following information on the pH of EW during pasteurization. Ayres and Slosberg (1949) readjusted the pH of fermented EW to 9.0 before flash pasteurization at 59.4°C. A patent by van Olphen (1953) claimed that pathogenic bacteria in EW could be destroyed by increasing the pH to 9–12, then pasteurizing at 40–55°C. Elleman (1955) referred to a similar process which called for adjusting the pH of EW to 10.5 with NH4OH, holding .

Effect of Salt Cement Filtrate on Subsurface Formations

Abstract A search was made of the literature to determine the erect of the ion content of cement filtrates on shale and clay mineral formations. The influence of the ions on solubility by the addition of salt is shown. Using formation samples, and applying a variety of brines and cement filtrates, flow rates and permeabilities are compared. Discussed are factors that limit the penetration of formations by cement filtrate. Introduction Salt has many unique properties for use in oilwell cementing. Ludwig described the general effects of salt on cement and the basic chemistry involved when cement reacts with sodium chloride in concentrations ranging up to saturation of the mixing water. Some qualities characteristic of salt, used in unspecified quantities for oilwell cementing, are that itimproves flow properties,is a good dispersing agent,is compatible with most other additives,acts as an accelerator in low concentrations and as a retarder in high concentrations,aids in expansion of set cements, andincreases slurry weight. Slagle and Smith reported, "the principal benefit of salt evolves not from its accelerating, dispersing or retarding properties but, rather, because of its influence on clay minerals, which represent a predominant portion of shales and exist in various quantities in sands and other producing formations". More recently a question was raised as to formation permeability damage by leak-off of salt cement filtrate. A search for answers to this question took the form of a survey of available literature and laboratory studies. The literature survey shows the effects on shale and other clay mineral-bearing formations of ions normally found in cement slurry filtrate. Several filtrates were used to determine the relative effect cement filtrate invasion can have on formation permeability, and whether or not deleterious reactions exist between formation constitutents and the ionic components of a filtrate. Effect of Ionic Environment On Bentonitic Formations Most researchers agree that permeability reduction in bentonitic sandstone occurs from two sources: swelling of clay minerals, and migration of dislodged particles to a constriction in the pore system. In his work with permeability of sandstone cores, Mungan concluded that the primary cause of permeability reduction is blocking of the pore by dispersed particles, and that permeability reduction due to salinity changes occurs regardless of the type of clay. The changes referred to here are changes in solutions containing no divalent cations such as calcium, and abrupt changes in concentration. Jones stated that an increase of salt concentrations in water tends to prevent clay blocking. He pointed out that clays in the calcium form do not disperse so easily in fresh water as do those in the sodium form. Jones concluded that cores capable of even severe clay blocking generally can conduct water as fresh as drinking water without significant change in permeability if at least one-tenth of the salts dissolved are calcium or magnesium salts, and if the salinity is decreased very gradually rather than abruptly. Hewitt concluded that a reduction in cation concentration by dilution promotes dispersion, and that the amount of swelling of each clay generally increases with a decrease in salinity of the surrounding fluid. He stated, "Therefore, a concentrated brine would cause the least damage; fresh water would cause the most." Van Olphen showed how Van der Waals attractive force is sufficient to overcome the repulsive forces of the electric double layer in bentonitic sols at high electrolyte concentrations, and thereby collapse the expanded clay particles. Foster, Savins and Waite showed this particle collapse by means of X-ray measurements of the distance between platelets, made at increasing salinities of solution (Fig. 1). JPT P. 259ˆ

X-Ray Study of Interactions between Montmorillonite Platelets

AbstractSmall angle X-ray scattering curves have been obtained for a series of Na Wyoming Bentonite clay samples containing 10% clay by weight and NaPO3 in concentrations ranging from 0 to 100 meq/1. From the scattering data, the relative probability of spacings between parallel clay platelets was computed. For the sample containing no NaPO3, the probability distribution showed a relatively broad maximum at an interparticle spacing of about 180Å. As the concentration of NaPO3 increased, the maximum became sharper and occurred for smaller interparticle distances. At NaPO3 concentrations between 25 and 100 meq/1, the position d of the maximum was given approximately by the equation d = 21 + 18.4c-1/2, where d is in angstroms, and c is the NaPOs concentration in eq/1. The similarity of this relation to the dependence of d on the concentration of NaCl (Norrish and Rausell-Colom, 1963; Norrish, 1954) suggests that the interparticle spacing depends primarily on the sodium ion concentration and not on the concentration of the anion. The value of d appears to be independent of whether the gel was prepared by the method of Norrish and Rausell-Colom, in which a dried flake was allowed to come to equilibrium with an electrolyte solution, or whether, as in this investigation, the gel was obtained by centrifuging a dilute suspension. Since the Na ions act to reduce the double-layer repulsion between platelets, while the anions tend to be adsorbed on the platelet edges and thus reduce the edge-to-face linkages (H. van Olphen, 1962), the value of the most probable interparticle distance appears to be determined primarily by the magnitude of the double-layer repulsion, even though other properties of the clay gels, such as the rheological behavior, are governed mainly by edge-to-face attractions.

An Introduction to Clay Colloid Chemistry. For clay technologists, geologists, and soil scientists. H. van Olphen. Interscience ( Wiley), New York, 1963. xvi + 301 pp. Illus. $10

An Introduction to Clay Colloid Chemistry. For clay technologists, geologists, and soil scientists. H. van Olphen. Interscience ( Wiley), New York, 1963. xvi + 301 pp. Illus. $10

An introduction to clay colloid chemistry. By H van Olphen. Interscience Publishers, Div. of John Wiley & Sons, 605 Third Ave., New York 16, N. Y, 1963. xvi + 301 pp. 15.5 × 23 cm. Price $10

An introduction to clay colloid chemistry. By H van Olphen. Interscience Publishers, Div. of John Wiley & Sons, 605 Third Ave., New York 16, N. Y, 1963. xvi + 301 pp. 15.5 × 23 cm. Price $10

Density Studies in Clay—Liquid Systems, Part II: Application to Core Analysis

AbstractIn Part I (Deeds and van Olphen, 1961) pycnometric data on expanding clays in water and in other displacement fluids were analyzed in terms of inaccessible void space within aggregates and of possible density anomalies of the adsorbed fraction of the displacement fluids.Further details of this work are reported, and the consequences for the interpretation of core analysis data are discussed. It is concluded that in core analysis the density of the connate water can be assumed to be normal while the fraction of the total pore space which is filled with oil is computed, provided that the total pore space is determined by using water or a polar organic liquid. If a hydrocarbon liquid or an inert gas is used, a small correction for inaccessible pore space can be applied.