bluuebunny/crossref_metadata_2025_split huggingface dataset:
VARIATION IN AGGRESSIVENESS AND AFLP AMONG Alternaria solani ISOLATES FROM INDONESIA
Authors: Chaerani Chaerani , Kardin M. Kosim , Suhardi Suhardi , Sofiari Eri , Van Ginkel Ria V. , Groenwolt Remmelt , Voorrips Roeland E. 
Published: January 2018

<p><em>Alternaria solani </em>is a necrotroph fungus that causes three-phased diseases in tomato. Management of the pathogen by using resistant cultivars requires knowledge on the aggressiveness and genetic diversity of the fungus. The aims of this study were to isolate <em>A. solani </em>from major tomato and potato producing areas in Indonesia and to study their aggressiveness and genetic variability. Twenty two<strong> </strong><em>A. solani</em><strong> </strong>isolates were recovered from early blighted tomato and potato in Central and West Java.<strong> </strong><em>A. alternata</em><strong> </strong>was also isolated from tomato leaves in West Java and North Sumatra, indicating that early blight in Indonesia may be caused by more than one <em>Alternaria </em>species. Resistance tests of four tomato genotypes to selected<strong> </strong><em>A. solani</em><strong> </strong>isolates revealed that local isolates were more aggressive in inciting early blight and stem lesion than an imported isolate from USA. This implies that introduced breeding materials must be tested to local isolates to obtain effective resistance genes. Cluster analysis based on amplified fragment length polymorphism (AFLP) obtained from <em>Eco</em>RI+AG and<strong> </strong><em>Mse</em>I+C primer amplification separated 28 local and Taiwan isolates from the US isolate, which was coincided with aggressiveness separation between the local isolates and the US isolate. Three clusters of AFLP genotypes which did not associate with geographic origin were observed among tropical isolates. The low genetic diversity among the Indonesian isolates suggests clonal population structure with wide distribution. Successful local tomato breeding requires the availability of local<strong> </strong><em>A. solani </em>collection with well-characterized aggressiveness level and molecular diversity to obtain effective resistance genes.</p>
SALINITY TOLERANCE OF SEVERAL RICE GENOTYPES AT SEEDLING STAGE
Authors: Safitri Heni , Purwoko Bambang Sapta , Dewi Iswari Saraswati , Ardie Sintho Wahyuning 
Published: January 2018

<p class="abstrakinggris">Salinity is one of the most serious problems in rice cultivation. Salinity drastically reduced plant growth and yield, especially at seedling stage. Several rice genotypes have been produced, but their tolerance to salinity has not yet been evaluated. The study aimed to evaluate salinity tolerance of rice genotypes at seedling stage. The glasshouse experiment was conducted at Cimanggu Experimental Station, Bogor, from April to May 2013. Thirteen rice genotypes and two check varieties, namely Pokkali (salt tolerant) and IR29 (salt sensitive) were tested at seedling stage. The experiment was arranged in a randomized complete block design with three replications and two factors, namely the levels of NaCl (0 and 120 mM) and 13 genotypes of rice. Rice seedlings were grown in the nutrient culture (hydroponic) supplemented with NaCl at different levels. The growth and salinity injury levels of the genotypes were recorded periodically. The results showed that salinity level of 120 mM NaCl reduced seedling growth of all rice genotypes, but the tolerant ones were survived after 14 days or until the sensitive check variety died. Based on the visual injury symptoms on the leaves, five genotypes, i.e. Dendang, Inpara 5, Inpari 29, IR77674-3B-8-2-2-14-4-AJY2, and IR81493-BBB-6-B- 2-1-2 were tolerant to 120 mM salinity level, while Inpara 4 was comparable to salt sensitive IR29. Hence, Inpara 4 could be used as a salinity sensitive genotype for future research of testing tolerant variety. Further evaluation is needed to confirm their salinity tolerance under field conditions. </p>
RELEASE OF SILICON FROM SILICATE MATERIALS AND ITS UPTAKE BY RICE PLANT
Authors: Anggria Linca , Husnain Husnain , Sato Kuniaki , Masunaga Tsugiyuki Masunaga 
Published: January 2018

<p class="abstrakinggris">Plants absorb silicon (Si) from soil solution in the form of monosilicic acid, also called orthosilicic acid (H<sub>4</sub>SiO<sub>4</sub>). Application of organic and inorganic materials containing readily soluble Si can increase Si supply in the soil and its uptake by plant. The study aimed to evaluate the release of Si from organic and inorganic material sources and its uptake by rice plant. The released phosphorus (P) from those materials was also evaluated. The inorganic materials evaluated included fly ash, steel slag, silica gel and Japanese silica gel (JSG), while the organic materials consisted of rice husk ash (RHA), rice husk burnt (RHB), media of mushroom (MM), cacao shell biochar (cacao SB) and rice straw compost (RSC). The dynamics of Si and P were observed by periodical samplings at 7, 17, 24 and 34 days after transplanting (DAT). Tiller number and plant height were measured at 16, 21 and 36 DAT. The results showed that Si concentration in solution derived from inorganic material was highest for JSG followed by silica gel (1.107 and 0.806 mmol L<sup>-1</sup>, respectively). The release of Si from organic material was higher for RHB and RHA (0.618 and 0.539 mmol L<sup>-1</sup>, respectively). Cacao SB, silica gel, JSG and RHB significantly increased plant height at 36 DAT. Meanwhile, Si materials did not significantly affect the tiller number. Of the materials used, steel slag and JSG significantly affected Si uptake by rice plant.</p>
Transient Cuttings Transport with Foam in Horizontal Wells-A Numerical Simulation Study for Applications in Depleted Reservoirs
Authors: Prasun Samir , Ghalambor Ali 
Published: January 2018

Abstract
A good knowledge of foam hydraulics and cuttings transport (hole cleaning) is essential for successful applications of foam drilling technology in horizontal wells. Estimating local fluid velocity in a partially blocked eccentric annulus (due to cuttings) is a challenge; so, a new analytical method of calculating local stress and velocity (near cuttings-bed in annulus) in an eccentric annular flow is derived which makes it possible to estimate the bed height for foam drilling in horizontal wells. Therefore, a new equation for local velocity (critical velocity) to initiate particle movement is used in order to predict the bed-height profile in a build-up or horizontal section of wellbore. This investigation also focuses on understanding the effects of drilling parameters on bed height and cuttings concentration.
A new transient wellbore hydraulics and cuttings transport model has been developed using the finite difference method of continuity equations for foam and cuttings. In order to predict the cuttings bed formation in horizontal wells, a mechanistic hole-cleaning model consisting of two layers has been utilized. The model is based on torque balance for a particle on the surface of a bed. In addition, a new model has been formulated for the local shear stress by modeling the eccentric annular flow as the infinite number of concentric annuli with variable outer radius. Similarly, using the narrow slot-approximation technique, a local velocity profile has been determined analytically in the eccentric annulus to be applied in the torque balance equations. Subsequently, model predictions of bed height were compared with published experimental data and the model is fine-tuned to minimize discrepancies.
Results show the cuttings bed front transitions through the annulus along the build-up and horizontal sections. Model predictions showed a good match with experimental results for concentric horizontal annulus except at higher polymer concentrations (greater than 0.25%). The simulation results show that bed height and cuttings concentration are quite sensitive to the changes in surface foam injection rates and back-pressure, thereby can be best optimized by properly adjusting these input parameters. The results also suggest that hole-cleaning is a function of inclination. The bed height increases with increase in inclination angle until a critical angle of 90°-φ (φ is the angle of repose) after which, it reduces.
Microbial Remediation of Guar-Based Fracturing Fluid Damage
Authors: Ma Xin , Lei Guanglun , Wang Zhihui , Da Qi'an , Song Ping , Zhang Xin , Yao Chuanjin 
Published: January 2018

Abstract
As the development of unconventional oil and gas reservoirs, hydraulic fracturing has become a critical component. However, formation damage is always impeding the application of hydraulic fracturing. A remediation method is presented that microbes can be used to remove the guar-based fracturing fluid damage. Laboratory experiment results show the feasibility and effectiveness of this method in different reservoir temperature.
This approach is based on the bio-degradation of guar gum. Guar gum degrading bacteria was isolated from the well water and identified through 16S rDNA. Apparent viscosity and average molecular weight were employed to measure the bio-degradation. The mechanism of microbial remediation of guar-based fracturing fluid damage was proved by the biodegradation of filter cake through measuring the thickness of filter cake on the filter paper. In addition, the core-flood simulation experiment was also conducted to verify the feasibility of this method. The experimental method is described in detail to permit readers to replicate all results.
Three guar gum degrading bacterial strains, Bacillus aerius, Anoxybacillus rupiensis and Geobacillusstearo thermophiles, were isolated and identified. Physiological-biochemical characteristics showed that the bacteria can grow in the oil reservoir with high temperature (50~70°C). In addition, the apparent viscosity and the average molecular weight of guar gum decreased significantly after bio-degradation. It means that the fluidity of guar gum residue rises. Bacillus aerius has the fastest degradation ability from 86.5 mPa·s to about 3.0 mPa·s for 48 h with the decrease of average molecular weight from 5.19×105 to about 4.53×104. Furtheremore, the thickness of filter cake was reduced by average 0.46 mm showing the signifiacant filter cake dissolving ability. Additionally, the permeability of sand-pack columns was restored up to 93.71% in laboratory simulation experiments. In conclusion, it is believed that the microbial treatment seems to be a new approach for remediation of guar-based fracturing fluid damage and has great potential in unconventional oil and gas development.
The novelty of the new method is in the ability to remove the polymeric damage using the bacteria when the formation was damaged after hydraulic fracturing.
Dispersion-Based Paraffin Inhibitors Adsorbed in Solid Substrates Affords Long Term Flow Assurance
Authors: DeBenedictis Frances , Bhaduri Sumit 
Published: January 2018

Abstract
Paraffin deposition, resulting in productivity loss of newly completed wells, is a major source of formation damage and is operationally and financially critical to address with a proven solution. Paraffin inhibitors included in the stimulation treatment have limited long term success due to cost and limitations on the amount of inhibitor that can be added to provide the desired longevity. A dispersion based paraffin inhibitor adsorbed on a high surface area substrate was developed which is compatible with fracturing fluids and affords a long term, cost effective solution to the paraffin deposition problem.
Laboratory studies were conducted under simulated field conditions, and the effect of inhibitor on oil properties (pour point, cold finger) as the oil is treated in the proppant pack with adsorbed paraffin inhibitor was investigated. Oils with different paraffinic issues were analyzed in this study. The studies estimate the longevity of treatment and the improvement expected using this treatment for field applications using flow-through column tests.
Traditional paraffin inhibitor treatments have provided limited long term performance in wells with paraffin issues. Little protection is provided beyond the perforations when continuously treating into the production fluids through capillary injectors. Additionally, squeeze treatments designed to increase the chemical's contact area by forcing the chemical treatments deeper into the reservoir give limited longevity in high paraffinic wells. In the current study, a novel treatment results in greater amounts of inhibitor placed downhole for prolonged treatment. A combination treatment was recommended whereby a compatible submicron-sized paraffin inhibitor dispersion is added to the fracturing fluid. In addition, a dispersion based paraffin inhibitor was adsorbed onto a proppant-like substrate that can be mixed into the proppant and delivered deep into the formation with fracturing or refracturing treatments, providing enhanced flow assurance management.
Well Assessment and Evaluation by Decomposition of Energy Dissipation
Authors: Chu Lifu , Ye Peng 
Published: January 2018

Abstract
Successful operation of an offshore field relies heavily on a surveillance program to monitor and describe the dynamic status of the wells. Conventionally, such programs consist of a series of shut-in and wrap-up procedures to collect essential buildup/drawdown pressures for inferring the near wellbore status, drainage volume, well productivity index (PI), etc.
Such surveillance programs are complex and expensive. They require long well shut-in periods, which may be infeasible both economically and operationally in certain scenarios. Although a long shut- in may be prohibitive, pressure buildup data from planned or unexpected short shut-ins are often available in offshore fields.
This paper presents an innovative methodology to infer the necessary information from short shut-in data. The main theoretical basis for the new method is the decomposition of the energy dissipation during the pseudosteady-state flow period. By decomposing the energy loss into time dependent and time invariant components, the dynamic status of the well(s) can be described using available plh drawdown (the pressure difference between one-hour shut-in pressure and flowing bottomhole pressure). The new method has been successfully used in offshore fields to: Create the evolution of the well skin and well PIsEstimate the well's drainage volumeDetect/confirm aquifer supportPinpoint the well workover/stimulation threshold and timingAssess the work quality of the workover/stimulation
This paper describes the theory and physics behind the methodology and demonstrates its application in an offshore field example.
Improving Well Productivity in North Kuwait Well by Optimizing Radial Drilling Procedures
Authors: Al-Jasmi Ahmad Kh. , Alsabee Ali , Al-Awad Ahmad , Attia Adel , Elsayed Abdou , El-Mougy Ahmed 
Published: January 2018

Abstract
Reservoir management requires continual efforts to identify opportunities for production enhancement. Radial Drilling (RD) technology is a method for production optimization by extending the contact area with reservoir. It utilizes hydraulic jetting energy to create several lateral holes within the zones of interest along different directions.
A candidate cased hole well-A was selected based on sub-normal production from a sandstone reservoir. Three extended laterals holes, at ±300 ft lengths each, are made using the RD technology. Job planning includes core studies, static and rotary jetting test using clean fluid. In order to avoid any possible formation damage during operations, RD job procedures have been optimized by using the different fluids mixtures during jetting, backwash and enlarging the created lateral holes. Jetting fluid used was brine mixed with NH4CL and Mutual Solvent, and followed by 10% HCL regular Acid.
The results showed a significant improvement in well productivity compared with previous well history. The post-treatment production test showed a ±110% gain in oil rate resulting from the improved reservoir deliverability. The dominant factor responsible for the success of this technology is the meticulous planning and testing before job execution. Moreover, it has proven to be an effective solution to bypass the deep damaged area around the sandface, and to improve the production recovery from heavy oil zones. The success of the new Radial Drilling technology with the optimized procedures can be implemented as a best practice in similar wells in north Kuwait fields.
This paper presents the advantages of the Radial Drilling technology in the recovery of bypassed crude oil from existing thin reservoirs, the optimized radial drilling procedures that ensured a clean lateral hole, and the evaluation of the impact compared to the conventional procedures.
The Effect of pH and Mineralogy on the Retention of Polymeric Scale Inhibitors on Carbonate Rocks for Precipitation Squeeze Treatments
Authors: Jarrahian Kh. , Sorbie K. S. , Singleton M. A. , Boak L. S. , Graham A. J. 
Published: January 2018

Abstract
The bulk "apparent adsorption" behavior (Γapp, vs. Cf) of 2 polymeric scale inhibitors (SI), PPCA and PFC, onto carbonate mineral substrates has been studied for initial solution pH values of pH 2, 4 and 6. The 2 carbonate minerals used, calcite and dolomite, are much more chemically reactive than sandstone minerals (e.g. quartz, feldspars, clays etc.) which have already been studied extensively. In nearly all cases, precipitates formed at higher SI concentrations were due to the formation of sparingly soluble SI/Ca complexes. A systematic study has been carried out on the SI/Ca precipitates formed, by applying both ESEM/EDX and particle size analysis (PSA), and this identifies the morphology and the approximate composition of the precipitates.
For PPCA, at all initial solution pH values, regions of pure adsorption (Γ) ([PPCA] &lt;100ppm) and coupled adsorption/ precipitation (Γ/Π) are clearly observed for both calcite and dolomite. PFC at pH = 4 and 6 also showed very similar behavior with a region of pure adsorption (Γ) for [PFC] &lt; 500ppm and a region of coupled adsorption/precipitation (Γ/Π) above this level. However, the PFC/calcite case at pH 2 showed only pure adsorption, while the PFC/dolomite case at pH 2 again showed coupled adsorption/ precipitation at higher PFC concentrations. For both SIs on both carbonate substrates, precipitation is the more dominant mechanism for SI retention than adsorption above a minimum concentration of ~100 – 500 ppm SI. The actual amount of precipitate formed varies from case to case, depending on the specific SI, substrate (calcite/dolomite) and initial pH (pH 2, 4 and 6).
Although the qualitative behavior of both PPCA and PFC was similar on both carbonate substrates, the apparent adsorption of PPCA was higher on calcite than on dolomite; PFC apparent adsorption was higher on dolomite than on calcite. It is discussed in the paper how these observations are related to the reactivity of the different carbonate minerals, the resulting final pH (which affects the dissociation of the SI), Ca-SI binding and the solubility of the resulting complex.
New Single-Phase Retarded Acid System Boosts Production after Acid Fracturing in Kazakhstan
Authors: Abdrazakov Dmitriy , Panga Mohan Kanaka , Daeffler Christopher , Tulebayev Duman 
Published: January 2018

Abstract
The use of conventional acid systems in high-temperature, fast-reactive carbonate reservoirs limits the effectiveness of matrix acidizing and acid fracturing. Therefore, during acid stimulation in such conditions, acids with retarded reaction are usually recommended. Industry-employed retarded acid systems have several significant drawbacks—they either dissolve lower rock volume or have higher friction and are more complex to mix than the standard hydrochloric acid system. The introduction of a new single-phase retarded acid enabled minimizing these drawbacks. The sustained increase in productivity index (PI) after the acid fracturing and matrix acidizing treatments under high-pressure/high-temperature conditions was achieved. The treatments were performed on exploration wells drilled in carbonate oil fields of the pre-Caspian and Mangystau oil-bearing provinces of West Kazakhstan.
Application of Polyelectrolyte Complex Nanoparticles to Increase the Lifetime of Poly Vinyl Sulfonate Scale Inhibitor
Authors: Veisi Masoumeh , Johnson Stephen , Peltier Karen , Berkland Cory , Liang Jenn-Tai , Barati Reza 
Published: January 2018

Abstract
Poly(vinyl sulfonate) (PVS) is an effective scale inhibitor in preventing the formation of barium sulfate. However, the low adsorption of PVS onto the rock results in a short squeeze treatment lifetime in reservoir. The application of nano-sized polyelectrolyte complexes (PECs) to increase the treatment lifetime of PVS is examined in this work.
Positively charged nanoparticles consisting of poly(ethyleneimine) and PVS were prepared. Sand pack studies were performed to quantify the adsorption and release of PEC-entrapped PVS, and the effect of ionic shock on the release of PEC-entrapped PVS was studied. It was found that an increase in the ionic strength of the displacing fluid released the PVS from the nanoparticle structure. Dynamic tube blocking tests showed that PEC-entrapped PVS increases the squeeze treatment lifetime by 22% compared to unentrapped PVS. The results also suggest that ionic shocks improve the release of PVS, prolonging the treatment by 40% compared to unentrapped PVS.
DISTRIBUTION OF BRYOZOANS IN VARIOUS FACIES OF EMSIAN SALAIR FORMATIONS
Authors: Мезенцева Ольга , Mezentseva Olga , Удодов Юрий , Udodov Yurii 
Published: January 2018

<p>The article analyzes the facial dissimilarity of bryozoans of the Emsian Stage near the town of Gyr’evsk. The bryozoans associations have been found in all types of facies, except the sand-mudstone one. In the littoral facies (bioclastic limestones with subordinate sand-mud-siltstones rock) the bryozoans are represented by the orders of <em>Trepostomida, Fenestellida, Cryptostomida, Cystoporida</em>, but treposomides predominate (63 % of the total number of species). After the littoral facies turn into the facies of the open lagoon (mudstones with subordinate limestones), only trepostomides are represented in the Emsian section, near the boundary, forming the Briozoan interbeds. Briozoan interbeds consist of the fragments of Neotrematopora salairiensis colonies. The restoration of species and genus diversity in new facies occurs relatively quickly. In comparison with trepostomides, representatives of other orders appear with a large time-lag. Under the conditions of an open lagoon, bryozoans are characterized mainly by branched bifoliate colonies. In the slope facies (bedded limestones), characterized by greater depths and low hydrodynamics, fennestellids dominate (58 % of the total number of species). Trepostomides and cystoporides in these facies are represented by species with thick-branched and massive branched colonies. When the facies of bedded limestones change to sandy-mudstones (the beginning of the regression), the fenestellids also form Briozoan interbeds near the boundary. In the lateral rows of the facies of a single stratigraphic unit, several facial associations of bryozoans are often found. The species of bryozoans characteristic of this stratigraphic level are present in all associations. The unity of the Emsian complex of bryozoans is expressed in the gradual change of their associations upwards the section (three Briozoanbiostratigraphic Zones have been <span>identified).</span></p>