bluuebunny/crossref_metadata_2025 huggingface dataset:
A Study of Some Factors Affecting Gun Perforating
Authors: Oliphant S.C. , Farris R. Floyd
Published: June 2014

Presented in this paper is a summary of the results of experiments conducted inboth the laboratory and the field during the past three years in connectionwith casing-perforation problems. Included are studies of gun features thatinfluence bullet performance and penetration, and studies of the effect ofperforator bullets on casing and the neat cement in the annulus. Discussion anddata are also presented relative to the accuracy of depth measurements in deepwells.

Introduction

It is a common practice in the oil industry to effect the completion of oilwells by setting and cementing casing through the production horizons andperforating the section of casing opposite the desired interval by means of agun lowered into the well on a cable or on the tubing. This practice has beenfollowed for some time, and this method of completion has been givenconsiderable study by the companies that render perforating service as well asby the oil companies that utilize their services. Through continued research onthis subject, it has been possible to develop guns, bullets, and powder thatwill permit controlled firing at great depths, and penetration of as many astwo strings of casing. It is the object of this paper to present the results ofstudies made of gun perforating in both the field and the laboratory. Thesestudies were made to determine the factors that affect penetration of thebullet, burring of the casing, accuracy of depth measurements, and other items.It is hoped that by presenting the results of these investigations a betterunderstanding may be obtained of certain of the factors involved in gunperforating and further investigation of the subject will be prompted.

Subsurface Tests

A well approximately 9000'Ft. deep, which was being prepared for abandonment, was selected for subsurface tests of gun-perforating experiments, In preparingthe well for the experiment, 5 ? in. casing in the hole was pulled and rackedin the derrick. A test section of pipe, which consisted of 65 ft. of 5 in. 18lb. J-55 casing centered inside 7 in. 28 lb. N-80 casing, was placed in thederrick corner and the annulus between the two pipes was cemented from thebottom up with 16 ? lb per gal neat cement, which was mixed and displaced witha cementing truck in the usual manner. After the cement had been allowed toharden for about a week, the test section was lowered into the hole in the 5 ?in. casing to a depth of 6600'Ft. by casing measurements. The hole was filledwith drilling fluid weighing 10 lb per gallon.

A perforating company was called to perforate the pipe, but was not advisedthat an experiment was being conducted.

T.P. 2115
Phase Behavior in the Methane-ethane-n-pentane System
Authors: Billman G.W. , Sage B.H. , Lacey W.N.
Published: June 2014

The composition of the coexisting phases in the methane-ethane-n-pentane systemwas determined at 100'F. This was accomplished by withdrawing samples of thecoexisting phases under isobaric-isothermal conditions. The relative amount ofeach of the components present in the liquid and gas phases was determined byconventional analytical fractionation methods. The phase behavior of thissystem approximates that estimated from generalized correlations which takeinto account the influence of the nature and amount of each of the componentspresent upon the equilibrium. It was found that for particular pressures andtemperatures the equilibrium constant of each of the components was influencedsignificantly by the composition of the system and this effect was morepronounced at the lower pressures for methane than for the components ofgreater molecular weight. However, at the higher pressures approaching themaximum two-phase pressure for the system at this temperature the compositionmarkedly influences the equilibrium constants of all the components at aparticular pressure and temperature. The results of this study are presented ingraphical and tabular form.

Introduction

The phase behavior of many of the binary systems containing paraffinhydrocarbon components from methane through n-pentane has been investigatedduring recent years. In addition the compositions of the coexisting phases inmixtures of crude oil and natural gas have been studied.

However, these results do not establish the influence of the nature and amountof the other substances making up a multicomponent system upon the gas-liquidequilibrium constant of anyone component. A preliminary correlation on thebasis of values for binary systems was made utilizing such experimentalinformation as was available. However, there is need for much additionalinformation regarding behavior in systems containing more than twocomponents.

Study of the phase behavior of ternary systems offers a feasible attack uponthe determination of the influence of composition as well as of pressure andtemperature upon the several equilibrium constants concerned. An investigationof the phase behavior of the methane-propane-n-pentane system at 100?, 160?, and 220'F was reported. This work served to illustrate the marked influence ofconcentration of the other components upon the equilibrium constants.Variations of as much as $0 pet in the equilibrium constants for methane forfixed temperature and pressure were observed in regions remote from thecritical state. Likewise there was a marked variation in the equilibriumconstants of propane and n-pentane as a result of changes in the composition.These results indicated the desirability of investigating additional ternarysystems. The present paper deals with a study of the methane-ethane-n- pentanesystem at 100'F, which is similar in many respects to the work upon themethane-propane-n-pentane system cited above.

T.P. 2232
Some Uses and Limitations of Model Studies in Cycling
Authors: Marshall D.L. , Oliver L.R.
Published: June 2014

The use of model studies for the development of invasion patterns for cyclingis illustrated by model studies obtained with a recently developed apparatus inthe solution of actual cycling problems.

Introduction

Depletion of a gas reservoir by cycling under pressure maintenance may bedivided into three general phases. In the first phase, injection of dry gas isused to move all possible wet gas to producing wells prior to breakthrough ofappreciable quantities of dry gas into producing wells. In the second phase, injection moves additional wet gas to producing wells while moderate quantitiesof dry gas are being produced. The third phase consists of production withoutinjection to deplete the commercial gas reserve which remains after the cyclingoperation. Thus, in the first phase, a portion of the reservoir is invaded bydry gas, and the dry gas usually displaces something less than 100 pct of thewet gas from the invaded portions of the reservoir. The second phase enlargesthe invaded portion of the reservoir and, at the same time, increases recoveryfrom that zone invaded by dry gas in the first phase of the cycling operation.The result is an early yield of a substantial quantity of the liquefiablehydrocarbons in the reservoir with a minimum of the retrograde losses whichoccur in some reservoirs. The overall recovery from such an operation isusually high.

The summation of the paths taken by dry gas in a cycling operation can betermed an invasion pattern. The use of electrical models to predict invasionpatterns has been the subject of several contributions to the literature, theresults of such model studies as applied to actual cases has been discussed byKelton and Miller and Lents.

Recently, an improved apparatus for conducting potentiometric model studies hasbeen developed, as described by Lee. S The purpose of this paper is to presentmodel studies or invasion patterns obtained with this instrument in thesolution of actual cycling problems.

The percentage of displacement of wet gas within the invaded portion of thereservoir in cycling, increase in recoveries of wet gas by continuing cyclingafter dry gas breakthrough, recoveries of wet and dry gas by production aftercycling, or economic factors in cycling are beyond the scope of this paper.Discussions which follow will be limited entirely to the development ofsuitable invasion patterns for cycling under pressure maintenance and the useof model studies therein.

T.P. 2230
Use of Oil-emulsion Mud in the Sivells Bend Field
Authors: Echols W.H.
Published: June 2014

An oil-emulsion mud, consisting of a mixture of oil-base mud and bentoniticwater-base mud, has been used experimentally in drilling 8 of the 35 wells inthe Sivells Bend field, Cooke County, Texas. Experience indicates theoil-emulsion mud can be controlled in much the same manner as a water-base mud, and the "drilling" functions of the two types of mud are comparable.The average water-loss for the oil-emulsion mud was 3.8 cu cm per well. Whenusing oil-emulsion mud to drill the last 2000'Ft of 7000'Ft wells, the mudcosts were approximately 2Y2 times that of water-base mud. There is nothing toindicate well productivities have been affected through the use of oil-emulsionmud. However, drilling time and bit footages were increased and the holes weremaintained more closely to bit guage. The apparent advantages gained throughthe use of oil-emulsion mud in the Sivells Bend field do not appear to justifythe increase in mud costs.

Introduction

Until a comparatively few years ago most of the development of drilling mud wasdirected toward improving the functions of the mud as related to actualdrilling operations. The industry has long recognized that one disadvantage ofrotary drilling over cable-tool drilling is the possibility of injury toproducing zones through the blocking effect resulting from the infiltration ofwater or mud into the sands. Recognizing this disadvantage, considerableattention has been diverted toward the development of muds that will improvethe quality of well completions through the reduction or elimination of waterinto the sands, but without sacrificing too many of their "drilling"functions and at a cost commensurate with the benefits derived from their use.This phase of mud research has already found practical application, forexample, in the development of the Rangely field, Colorado, it appears the useof oil-base mud during drilling-in operations will contribute appreciablytoward making this exploitation more profitable.

Much of the discussion to follow will be better understood if a brief sketch ofthe Sivells Bend field is given. The Sivells Bend field, discovered by TheTexas Co. in 1944 and still in the process of development, is in a large bendon the Texas side of the Red River about 85 miles north of Dallas.Geologically, the structure is an unsymmetrical anticline, with faulting havingcontributed to its development. The productive sands are of the Strawn seriesof Pennsylvanian age, the sands being lenticular in character and varyingconsiderably in development from well to well. At present there are 35producing wells in the field, producing from seven different sand lenses. Theproductive sand lenses vary from 15 to 50'Ft in thickness and the individualsands have average permeabilities of from 75 to 375 md.

T.P.2227
What Does Industry Have a Right to Expect of Petroleum Engineering Schools?
Authors: Bohart P.H.
Published: June 2014

The answer to the title question will be found by considering the ultimateinfluence of the petroleum engineers on industry and by considering the toolswith which petroleum engineers must be equipped. Some 2000 to 3000 petroleumengineers are being absorbed by the industry yearly, indicating the magnitudeof influence which they may exert on the industry.

The petroleum industry is a highly technical one and it is inevitable thatmanagement be entrusted more and more to executives with technical training.The industry, therefore, expects the petroleum engineering schools to provide abroad basic training and a social and economic orientation which goes beyondmerely supplying the minimum technical qualifications necessary to dischargeresponsibilities for a particular job. Because of the many branches ofindustry, emphasis must be placed on the student's being trained infundamentals, as well as grounded in other engineering branches, such asmechanical, civil and electrical engineering. The petroleum engineeringgraduate must know how to outline and organize the material for an engineeringreport and should be thoroughly grounded in English, both written andspoken.

Even to the end that a five-year course may be required, they should receiveinstructions in auxiliary cultural and social science courses, industrialrelations, and public speaking. Training in the method of approach to anengineering problem is something in which industry is deeply interested. Astandard of ethics, a desire to arrive at the truth, and leadership trainingshould be stressed.

Introduction

The basis of an answer to any question concerning the petroleum engineeringschools' responsibility to the industry will be found by considering theultimate influence of the petroleum engineers on the industry and byconsidering also the tools with which petroleum engineers must be equipped inorder to achieve success and happiness in the role in which their training, individual talents and choice of a profession ultimately will cast them. Theproblem must always be considered as it relates to a large group and not as itrelates to a particular individual possessing strong natural talents anddestined, by virtue of them, to pursue a certain course.

The question implies that petroleum engineering schools have a responsibility, and indeed they do, not only to the industry but also to the students and evento the public. Because the responsibility is concentrated in a relatively fewschools whose graduates are absorbed largely by the one industry, theresponsibility is more apparent and the effect of failure to discharge theresponsibility fully is more serious than the effect of similar failure on thepart of schools supplying a smaller portion of the industry's intake ofengineering graduates. This fact is especially true with respect to an industrysuch as the petroleum industry whose ratio of technical to nontechnicalemployees is relatively high and is increasing.

T.P. 2270
Calculation of Initial Fluid Distributions in Oil Reservoirs
Authors: Muskat Morris
Published: June 2014

It is pointed out that the application of capillary pressure curves obtainedby drainage or desaturation processes to the calculation of the fluiddistribution in interphase transition zones involves a number of difficulties;namely:the development of very low nonwetting phase saturations appears tobe in contradiction with the lack of mobility of such distributions indicatedby permeability-saturation curves,dispersed non wetting phases arethermodynamically unstable, anddiscontinuous phases should not be subjectto hydrostatic equilibrium requirements.

While these difficulties could beobviated by assuming that the capillary pressure drainage curve has an initialhorizontal segment, they are automatically circumvented by application of theimbibition capillary pressure curve to the lower part of the water-oiltransition zone. These generally show zero displacement pressure at onlypartial wetting-phase saturations. The countercurrent upward flow of oil intothe main oil-saturated pay and downward drainage of water also suggests thatwetting-phase imbibition processes will control the saturation distributionimmediately above the water-saturated section. Similar considerations, with ageneralized interpretation of the apparent wetting-phase behavior of the oiland gas phases, provides a basis for constructing the curve for fluiddistribution in the oil-gas transition zone. In the transition zones soderived, the oil begins with a nonvanishing saturation at the water-oil contactand terminates with a similar saturation at the top of the gas-oil contact. Thegas-oil transition zone begins with an equivalent nonvanishing gassaturation.

Introduction

It has been a common assumption for some years that the nature of the fluiddistribution in virgin reservoirs, and in particular that in the transitionzones between the oil and water and between the oil and gas sections, can becomputed by a simple application of capillary pressure data. The results ofsuch calculations appear to have been first reported by Leverett. The latter, however, indicated only the numerical values of the parameters used in thecomputations, without explicitly describing the procedure. Leverett'sillustrative calculated transition zones are reproduced in Fig 1. Although nocritical study of the apparently obvious method of calculation has beenpublished, one cannot proceed very far in the computation without encounteringsome rather fundamental questions not yet answered in the literature.

This paper is not written under the pretense that the whole transition-zoneproblem has been fully and satisfactorily solved. Its purpose, rather, is todiscuss suggestions for its treatment, much of it admittedly hypothetical, andemphasize the nature of the uncertainties arising therein; for the literature, as now available, gives little indication that there are any problems stilloutstanding.

T.P. 2405
Displacement of Oil from Porous Media by Water or Gas
Authors: Welge Henry J.
Published: June 2014

Laboratory apparatus has been devised which permits study of the displacementof oil from cores by water and by gas. The cores used contained interstitialbrine as well as oil.

Experiments were run to determine the comparative effect of varying theproperties of the fluids used. No great effect was noted on the maximumdisplacement achieved. This observation made it unnecessary in initial work touse fluids in their exact reservoir conditions. Consequently, the displacementswere run at near-atmospheric pressure in Pyrex glass equipment, using strippedcrude oils.

Introduction and Theory

The chief object of this work has been to determine the efficiency of gasand water as primary agents for displacing oil from reservoir rock underlaboratory conditions in which capillary phenomena were predominant. To thisend the maximum displacement of oil from cores has been ascertained. Thismaximum displacement may not be equal to the maximum displacement from areservoir; but it will he a close approximation to it sometimes, and othertimes the laboratory information will be useful in reservoir engineeringpredictions. It is believed that the laboratory experimental maximum representsthe upper limit for the reservoir recovery.

The experiments were carried out by obtaining cores of interest from thereservoir, and filling the pores with interstitial brine and oil with therestored state technique. Then the oil was displaced from the core as describedlater, either by brine from below, or by gas from above. The former type ofdisplacement suggests analogy to production by water drive, but not to waterflooding, for reasons discussed below. The latter type of displacement isbelieved to simulate production by gas cap displacement.

The displacements were performed by what may be termed thecapillary-pressure method. The cores are placed in capillary contact with anoil-wetted membrane which has very small pores (about I micron in diameter).Pores of this size will transmit oil hut prevent the passage of gas or water, unless the pressures used are higher than the capillary pressures employed inthis work. Accordingly, use of the membrane makes it possible to apply acapillary pressure differential between the displacing phase and the oil in thecore.

T.P. 2433
Experimental Production Projects and Exploratory Drilling at Elk Hills
Authors: Eastman Max C. , Ruhlman F.L.
Published: June 2014

The termination of the recent war marked a major change in the oil-fieldoperations at Elk Hills. Production was greatly curtailed, various experimentalproduction projects were started, and a long-range exploratory program wasinaugurated. Production was reduced from the wartime peak of 65,000 bbl per dayto the current rate of about 8000 bbl per day in order to maintain an availablesource of crude that can be drawn upon during a national emergency. Theexisting production rate is deemed essential to carry on the experimentalproduction projects. These projects are being conducted to determine the bestmethods and means of maintaining the Reserve, shut in; but in a state ofreadiness to produce the maximum quantity of oil in the most expeditiousmanner. Projects now being investigated include:protection of surfaceequipment;repair of wells that might damage the reservoir;gasinjection;water encroachment,gravity drainage.

An exploratory program is being carried on to determine the amount ofrecoverable oil in the unexplored portions of the Reserve. The Shallow-zoneexploration is practically completed, but owing to the complexity of theStevens structure and the magnitude of the oil discoveries in the Stevens, exploration will probably continue in that zone for another two years.

Introduction

Summary of Development History of Elk Hills

Although a detailed history of Elk Hills oil field is presented in variouspublications, a summary of its unusual development and production history willbe given in order that the present problems may be more readily understood.

The first development that resulted in commercial production was in thecentral part of the Reserve. The first well, Hay No. I, in sec 36-R, wascompleted in January 1919, and was soon followed by 47 others in the samegeneral area. It is commonly referred to as the Hay-Carman area and was shut inin stages from 1925 to 1934 as a result of litigation regarding the title tothe land. Not being highly productive, only about 6 1/2 million barrels of oilwith a large volume of gas was produced from the area prior to theshutdown.

T.P. 2404
Group Risk Assessment Conversation and Experience Transfer (GRACE)
Authors: Vassmyr K.-A. , Gjellestad B. , Hide A.
Published: June 2014

The improved trend in number of injuries in the Norwegian Continental Shelf over the last decades is encouraging. Despite the improved statistics, it is a common goal to further reduce the number of injuries. One of the challenges is to learn from previous accidents.

The accident investigation reports or accident databases can be more proactively used by the workforce or management at site in terms of learning. However, such reports are often complicated and not easily available.

This paper presents the development of GRACE, a system that makes experiences from accidents available in a much more accessible format. Real accidents are presented in a format purpose built for experience transfer among first level leaders and their work force, with emphasis on visual presentation. The paper also outlines experiences in using the system.
Working Together With Subcontractors Towards Excellence in Quality, Health, Safety, and Environmental Issues
Authors: Alary F.
Published: June 2014

The contribution of subcontractors to oilfield service operations in Mexico has almost doubled over the last five years. Historically, the role of subcontractors was mainly limited to logistical or peripheral activities, but with the growth of integrated projects, they contribute directly to oilfield service operations, including well construction activities. In order to continue overall performance improvements in health, safety, environment, and service quality areas, it is critical to proactively manage interactions with our subcontractors so that risks are systematically identified and adequately controlled.

This paper gives an overview of a subcontractor management initiative, implemented in Mexico during 2004 and 2005 that enhanced the interfaces between a service company and its subcontractors. The initiative defined risk-based subcontractor selection and classification criteria, established clear roles and responsibilities, formalized performance and compliance expectations contractually, and implemented systematic monitoring processes to ensure compliance and evaluate performance. Similarly, specific efforts were made to develop the maturity of quality, health, safety, and environmental (QHSE) systems and the cultures of certain subcontractors by providing assistance, including training and coaching.

Contracting services and buying products have always been strategic components of oil and gas company operations because of the direct and critical impact on project technical performance and economics. Until recently, this dimension has not represented the same criticality for oilfield service companies like Schlumberger who are accustomed to working as contractors. This was largely due to a more limited exposure and a natural tendency to give absolute priority to the commercial and technical relationship with their clients, without necessarily realizing how much their own performance can be influenced by that of their subcontractors.
Evaluation of Experiment Program 2004: Natural Hydrate Exploration Campaign in the Nankai-Trough Offshore Japan
Authors: Matsuzawa M. , Umezu S. , Yamamoto K.
Published: June 2014

Ministry of Economy, Trade and Industry (METI) of Japan has decided to carry out the 16 years research and development program of natural methane hydrate (MH) resources and set up the Research Consortium for Methane Hydrate Resources in Japan (MH21) in 2001.1

In 2004, a multi-well exploration campaign in the Nankai-Trough was conducted as a national project led by METI. It was organized by Japan Oil, Gas and Metals National Corporation (JOGMEC) in collaboration with Japan Petroleum Exploration Co., Ltd. (JAPEX) and Teikoku Oil Co., Ltd. (TOC) as drilling operators. All scheduled programs were performed with deepwater research vessel "JOIDES Resolution" operated by Transocean. There were 30 wells drilled mainly for geological research purposes and 2 wells drilled for engineering experiment purposes during this campaign.2

The purpose of experiment was to obtain the engineering data and to verify technologies which would be required for the future possible production from the natural hydrate offshore of Japan. The following experiments, which were 1) Drilling fluids applicability for borehole stability, 2) Monitoring the downhole pressure and temperature while drilling, 3) Cementing, 4) Formation / fracture pressure measurements, 5) Capability to horizontally drill unconsolidated formations and hydrate layers in very shallow section below the seabed, was conducted by drilling 2 wells in 19 days. This experiment program was undertaken by Japan Drilling Co., Ltd. (JDC) under contract with JOGMEC for the planning and for the analysis of obtained data, and with JAPEX for the operation.

As a result of the experiment, effectiveness of the drilling fluids which were used to the borehole stability was confirmed. The specially designed cement slurry covered up the hydrate formations. The pressure measurement executed at several points including the hydrate formations by using Cased Hole Dynamics Tester (CHDT*) acquired effective data. The horizontal well was executed almost on the planned path and it was able to drill about 300m length of the hydrate layers including 100m length of horizontal section at 340mTVD below the seabed.

A further research and development is scheduled to be promoted with the method of completion of the production test well.
An Environment Friendly and Economically Attractive Thermal Degradation Inhibitor for Bentonite Mud
Authors: Amanullah Md.
Published: June 2014

The environmental concerns, increasing cost of exploration and the technical requirement of high temperature drilling demand the use of environment friendly, economically attractive and thermally stable water-based drilling mud to fulfill the functional behavior of a mud system to complete a well safely and economically. Thermal stability of low cost water-based mud is essential to achieve the technical goal, meet the environmental challenges and reduce the mud cost. This paper describes a novel additive to prevent the thermal degradation of bentonite mud up to a bottom hole temperature of 150°C.

The experimental data of a base bentonite mud showed more than 150% increase in PV, more than 250% increase in YP and more than 100% increase in gel strength after hot rolling at 150°C for 16 hours. The bentonite mud with novel thermal degradation inhibitor showed about 50% increase in PV and little change in the YP and gel strength characteristic of the bentonite+GSP mud after hot rolling at 150°C for 16 hours. The environment friendly thermal degradation inhibitor is expected to increase the working temperature range of bentonite mud without causing any damage to the environment.
Evaluation of Latest Techniques for Remedial Treatment of Scale Depositions in Petroleum Wells
Authors: Gholinezhad J.
Published: June 2014

A major phenomenon altering well productivity is increasing water production. In addition to raising energy consumption, higher water production leads to phenomena such as mineral and organic scaling, which may temporarily or even permanently alter the whole flow assurance chain. The buildup of scale inside well bore can smother a productive well within 24 hours, causing millions of dollars in damage every year.

A project was carried out to review and to evaluate new techniques and tools developed for scale treatments in order to find an appropriate tool, at least deployed with wireline rather than with coiled tubing (CT) to overcome the adverse scale problems encountered in most of the fields. This paper presents results of this evaluation and shows the advantages and disadvantages of different tools for scale removal process. Solid blasters, deployed with CT, have proved to be efficient in removing most of the scales but it is costly as well as inapplicable to wellbore and near-wellbore. Tools using fluidic oscillator technology is not that expensive, however they are not strong enough to treat very hard scales like barium sulphate. In addition, these tools have great standoff distances and are deployed with CT. String shots, wireline-deployed, are good for short intervals, thin layers of scales. Recent techniques, which use acoustic waves to clean the near wellbore damage are not good tools to be applied for tubing and casing scale depositions since they have only proved to have the ability to remove fines and soft materials like mud cakes from near wellbore region.
Fuel potential of faecal sludge: calorific value results from Uganda, Ghana and Senegal
Authors: Muspratt A. Murray , Nakato T. , Niwagaba C. , Dione H. , Kang J. , Stupin L. , Regulinski J. , Mbéguéré M. , Strande L.
Published: June 2014

This research tested the viability of using faecal sludge (FS) as solid fuel – an end use that could unlock an environmentally and financially beneficial replacement for disposal-oriented FS management, while replacing fossil energy. FS samples were collected from pit latrines, septic tanks, drying beds and stabilization ponds in three cities, Kumasi, Dakar and Kampala. For each sample, the average calorific value, solids and water content, and their variation with source and age were determined. The average calorific value of untreated FS across the three cities was 17.3 MJ/kg total solids (TS), which compares well with other biomass fuels. The age of FS did not affect its calorific value, nor did the reduction in chemical oxygen demand (COD) that occurred while it was in drying beds. The TS content of FS depended on its source but ranged from 1 to 6% for sludge from septic tanks and pit latrines, respectively. Harnessing net energy from FS requires partial drying. The results indicate that sufficient drying occurs within two weeks in open-air drying beds, or in a matter of days with simple drying bed innovations.
Rethinking public toilet technologies in Nairobi: the case of Ikotoilet facilities
Authors: Njeru Jeremia Nyaga
Published: June 2014

Although shared sanitation facilities have received low priority in the UN Millennium Development Goals, there is a growing recognition that these facilities should be central to sanitation interventions in the developing world. Accompanying this recognition is a realization that new and existing sanitation technologies must necessarily be customized to ensure that the safety and hygiene of such facilities is sufficiently sustained. In line with this recognition, this article highlights how ‘Ikotoilets’, the nationally and internationally acclaimed public toilets in Nairobi, Kenya, are providing reasonably hygienic and safe sanitation, largely due to a rethinking of the local technologies of shared sanitation. Drawing from a qualitative analysis of a ‘convenience’ survey of Ikotoilet users, interview with the provider of Ikotoilets, field observations, and published papers and reports, the article shows that since Ikotoilets are designed to incorporate different uses, blend into the existing urban landscape, and are installed with technologies which, among other things, reduce use of scarce resources, the facilities are contributing to sanitation solutions in the city.
The neglect of hygiene promotion in developing countries, as shown by the Global Analysis and Assessment of Sanitation and Drinking-Water survey
Authors: Jiménez Alejandro , Cavill Sue , Cairncross Sandy
Published: June 2014

The UN-Water Global Analysis and Assessment of Sanitation and Drinking-Water (GLAAS) report is one of the three periodic UN reports dealing with water supply, sanitation and hygiene. This paper analyses the data on hygiene promotion which were collected for the 2012 edition, but not included in the report. Despite the limitations of the information, this is the best picture available of the global status of hygiene promotion in developing countries. Results show the low priority given to hygiene when it comes to implementation. On average, the staff in place meets 40% of the estimated needs to achieve national targets. Countries report that over 60% of their population is reached by hygiene promotion messages, but we estimate that there are barely enough hygiene promoters to reach 10% of the people. Government officials' greatest concerns are the lack of human resources and funds, but they also point to the absence of strategy, responsible agency and basic coordination and monitoring mechanisms as challenges. This has serious implications for the poor working conditions and low recognition of hundreds of thousands of hygiene promoters, who in most cases are women capable of playing a crucial role for public health. There is an urgent need for further development of capacity for hygiene promotion in developing countries.
Phenol composition, DPPH radical scavenging and antimicrobial activity of cornelian cherry (Cornus mas) fruit and leaf extracts
Authors: Milenkovic-Andjelkovic Ana , Andjelkovic Marko , Radovanovic Aleksandra , Radovanovic Blaga , Nikolic Vesna
Published: June 2014

Fruit is rich in different phenolic compounds which are recognized as
potential natural medicaments and have been used in folk medicine for
centuries. In order to evaluate phenol composition, cornelian cherry (Cornus
mas) fruit and leaf extracts were subjected to the spectrophotometric and
HPLC analysis. The radical scavenging activity was estimated using DPPH test
and antimicrobial activity by disc diffusion and microwell dilution tests.
All extracts showed high phenol content from 89.89 ? 0.45 to 117.34 ? 1.40 mg
f gallic acid equivalents GAE/g extract dry matter DM but different
composition of phenol compounds. Flavonols, anthocyanins, flavan-3-ols and
phenolic acids were the main phenol classes found in the investigated fruit
and leaf extracts. All extracts showed significant radical scavenging
activity and a correlation with total phenol content (R2 = 0.9832).
Significant antimicrobial activity was found against Gram-positive, followed
by Gram-negative strains, and yeast in all tested extracts. Cornelian cherry
fruit and leaf extracts, rich in phenolic content, with significant
antiradical and antimicrobial activity, can be used as additives in food and
medicaments.
Separation of mineral oil droplets using polypropylene fibre bed coalescence
Authors: Govedarica Dragan , Secerov-Sokolovic Radmila , Kiralj Arpad , Govedarica Olga , Sokolovic Dunja , Hadnadjev-Kostic Milica
Published: June 2014

This paper investigates the separation possibilities of model emulsion
oil-in-water using polypropylene fibre bed coalescence. Experiments were
carried out over a wide range of physico-chemical characteristics of mineral
oils, bed permeability and operating fluid velocities. The aim of this study
was to analyse the influence of the dispersed oil phase nature and of the bed
geometry on the separation efficiency. From the obtained results, it can be
concluded that polypropylene fibres in the broadest studied range of bed
permeabilities and fluid velocities, effectively separate oil that is highly
polar. On the contrary, for the other two investigated oils at low values of
bed permeability a region was detected in which the coalescer is incapable to
operate. It has to be emphasized that the polypropylene fibres efficiently
separate all three investigated oils at the highest studied bed permeability.
Entropy change of open thermodynamic systems in self-organizing processes
Authors: Popovic Marko
Published: June 2014

The thermodynamic models available in the literature predict that during
self-organizing processes the entropy of a cell considered as an open
thermodynamic system decreases. This prediction leads to conclusion that cell
imports a certain amount of negative entropy and generates entropy during
irreversible metabolic processes. The controversial concept of negentropy was
criticized recently. In this research a new model was proposed that isn?t
based on the steady state approximation and describes living systems more
realistically. The analysis of the suggested model of an open thermodynamic
system far from equilibrium, led to the conclusion that the entropy during
self-organizing processes increases during growth (of a molecule or a cell).
Using as models the synthesis of an oligopeptide and a growing hydrocarbon
chain, it was shown that entropy of an open thermodynamic system increases
during addition of monomers (a self-organizing process). A derived equation
confirms the results obtained by calculations with literature experimental
values of molar entropy. The decrease of entropy observed in self-organizing
processes occurred only during phase transition.
Selection of a course of action by obstacle employment group based on a fuzzy logic system
Authors: Pamucar Dragan , Bozanic Darko , Milic Aleksandar
Published: June 2014

The paper has focused on the point at which a decision is to be made to
activate the Obstacle Employment Group (OEG), which is a defining moment for
the overall engagement of the group. The course of action is selected based
on a Fuzzy Logic System (FLS), created by translating the experience of
decision-makers into a single knowledge base. The FLS mainstays are four
input criteria and one output, interconnected by a rule base.
Economic Aspects of Reducing Stocking Density in Broiler Chicken Production using the Example of Farms in Southern Poland
Authors: Utnik-Banaś Katarzyna , Żmija Janusz , Sowula-Skrzyñska Elżbieta
Published: June 2014

The purpose of this paper was to assess the impact of reducing stocking density to the level recommended by Council Directive 2007/43/EC on broiler production profitability. The study was carried out using the example of three broiler-only farms located in southern Poland. The farms with production area of 950 m2, 3 400 m2 and 5 040 m2, had fully automated systems for feeding, watering and ventilation. In total, the research covered 54 production rounds in the years 2009–2011. research material included data concerning production costs and achieved production results, as well as income obtained in individual rounds. Net income from broiler production was calculated for three variants differing in stocking density: variant 1 – actual stocking density in farms in 2009 (47–45 kgm–2), variant 2 – stocking density of 42 kg m–2, variant 3 – stocking density of 33 kg m–2. the study results indicate that reducing stocking density increases total production costs, and decreases broiler production income. Production profitability depended primarily on the relation between prices of broiler livestock and feed. Reducing stocking density to the level recommended by the European commission (33 kg m–2) in 2009 would result in decrease of income from €2.40 to 0.77 per m–2, whereas in 2011 production carried out at this stocking density would result in losses. To maintain the current income level of farmers, it would require an increase of 5–6% in meat prices.
Assessment of Sexual Activity Levels and Their Association with Ejaculate Parameters in Two-Breed Hybrids and Purebred Duroc and Pietrain Boars
Authors: Wysokiñsk Anna , Kondracki Stanisław
Published: June 2014

The aim of the present study was to analyse sexual activity levels of two purebred boars (pietrain and Duroc) in comparison with two-breed hybrid boars (Duroc♀ × Pietrain♂ and Pietrain♀ × × Duroc♂) and to assess the relationship between the ejaculate parameters and the sexual activity of the animals. the experimental material was constituted by 20 boars. sexual activity measurements were performed in 4 different collection periods for each boar. The first libido analysis was carried out during the first week of insemination use, followed by the next analyses after 3, 6 and 9 months of service. In parallel to the sexual activity analyses, ejaculates were collected to investigate ejaculatory efficiency, physical characteristics of the ejaculates and sperm morphology. It has been shown that the characteristics of sexual activity parameters are affected by the breed of the boar and the crossbreeding variant. Two-breed sires are quicker to leap onto the phantom as compared with purebred boars. Duroc♀ × Pietrain♂ boars are characterized by a short period of time between phantom mounting and ejaculation initiation. On the other hand, they yield ejaculates for a much longer time than hybrid Pietrain♀ × Duroc♂ boars and purebred Duroc and Pietrain boars. Hybrid boar ejaculates contain more spermatozoa and can provide more inseminationdoses than ejaculates of purebred boars. Ejaculate parameters are chiefly correlated with ejaculation time and copulation duration. In our study the ejaculate parameters (ejaculate volume, sperm concentration and sperm motility) in purebred boars mainly depended on ejaculation time and total copulation duration, whereas in two-breed hybrids they were more affected by the length of the period between phantom mounting and the start of ejaculation.
Effect of Piglet Birth Weight on Selected Characteristics of Pork
Authors: Rekiel Anna , Bartosik Justyna , Więcek Justyna , Batorska Martyna , Kuczyńska Beata , Łojek Anna
Published: June 2014

The objective of the study was to determine how different birth weights of piglets influence some chemical and physical characteristics of pig meat. Piglets were grouped according to birth weight: ≤1.30 kg (group I), 1.31-1.70 kg (group II), ≥1.71 kg (group III). Animals were reared and fattened under standardized housing and feeding conditions. Tests were conducted with 60 samples of meat (20 per group) collected from the right side of the carcasses (M. longissimus lumborum) of threebreed crosses of (Polish Landrace × Polish Large White) × Duroc (barrows to gilts, 1:1), which were slaughtered at about 180 days of age. Determinations were made of basic chemical composition, colour of meat, drip loss, shear force value, and fatty acid profile. It was found that the birth weight of the piglets affects meat colour (redness), crude fat content and the proportion of some fatty acids (C16:1, C20:1 n-9, C20:2 n-6, C20:5 n-3).
Composition, Physical and Technological Properties of Raw Milk as Affected by Cattle Breed, Season and Type of Diet
Authors: Křížová Ludmila , Hanuš Oto , Hadrová Sylvie , Kučera Josef , Samková Eva , Roubal Petr , Veselý Aleá
Published: June 2014

The aim of the study was to describe the differences in composition, physical and technological properties of raw milk as affected by breed of cattle, season and type of feeding. The study was conducted from June 2005 to February 2007 on bulk milk samples (BMS) collected from 8 commercial dairy herds consisting of Czech Fleckvieh (CF, 4 herds) and Holstein (H, 4 herds) dairy cows. Half of herds in each breed was grazing (G) during summer season while the other half was not (N). Samples were collected regularly two times in winter (W) and two times in summer (S) period resulting in a total of 64 bulk milk samples (BMS) examined. Milk yield in CF (5385.50 kg) was lower (P<0.05) than in H (7015.15 kg). Milk fat in CF was higher (P<0.05) than in H breed being 3.9 and 3.72 g/100 g, respectively. CF cows had higher (P<0.05) content of crude protein, casein, true protein and non-protein nitrogen (NPN) than H. Content of fat, crude protein, casein, true protein and whey protein was lower (P<0.05) in summer (S) than in winter (W). Milk yield in grazing herds (G, 5197.50 kg) was lower (P<0.05) than in non-grazing herds (N, 7203.75 kg). Content of fat was higher (P<0.05) in G (3.89 g/100 g) than in N (3.73 g/100 g). Concentration of lactose, urea, crude protein, casein, true protein, whey protein was lower (P<0.05) in G than in N. In conclusion, the Czech Fleckvieh breed had a lower milk yield but produced milk with higher concentration of the main milk components than the Czech population of the Holstein breed. Large seasonal variations were determined in concentrations of the main milk components. The most pronounced changes in milk composition were caused by the type of feeding with a clear decrease in milk yield and content of lactose and all studied protein fractions and higher content of fat in grazing herds compared to non-grazing herds.
Body Condition Scoring and Obesity in Captive African Side-Neck Turtles (Pelomedusidae)
Authors: Rawski Mateusz , Józefiak Damian
Published: June 2014

African side-neck turtles (Pelomedusa subrufa and Pelusios castaneus) are popular in captivity, in many parts of the world. their natural tendency to accumulate body fat reserves may be a reason for many health issues. for keepers and veterinarians body condition scoring is an important tool in the process of management and care of the animals. therefore the main aim of the study was to formulate a single mathematic formula for allometric equations and simple body condition scoring method which can be used in juvenile, sub-adult and adult specimens of Pelomedusa subrufa and Pelusios castaneus. twelve healthy turtles (7 Pelomedusa subrufa and 5 Pelusios castaneus) – 4 males, 4 females and 4 immature were measured and weighed for 52 weeks (624 measurements). the obtained data were used to formulate equations of estimated body weight and compared to results of measurements of 73 turtles from private keepers. additionally, visual assessments of their body condition were made. The results showed that body weight is significantly (P=0.001) correlated with straight carapace length of turtles. in the assessed population of 73 captive Pelomedusidae kept as pets, no emaciated turtles were recorded, and 10% of them were underweight. In the case of 68% of the animals, body condition was identified as optimal, and in 15% and 7% as overweight and obese, respectively. The population of african side-neck turtles seems to be in quite good body condition. However, a high percentage of overweight and obese animals suggests the need for continuous monitoring of pet turtles for body condition.