bluuebunny/crossref_metadata_2025_split huggingface dataset:
Weighted Frac Fluids for Lower-Surface Treating Pressures
Authors: Simms Lloyd , Clarkson Brad , Navaira Gilbert 
Published: February 2008

Abstract
With Gulf of Mexico (GOM) hydrocarbon discoveries reaching record depths and very high bottomhole pressures, the need for proven, weighted fracturing stimulation fluids has become urgent. As previous studies have shown, frac packs have a significant impact in maintaining well productivity in the later production life stages of unconsolidated reservoirs. Thus, sustaining the ability to pump frac packs in these challenging environments is a priority.
With conventional frac pack fluids, these greater depths and higher bottomhole pressures often would result in the need for surface treating pressures that exceed the limits of current surface equipment and tubulars. Surface treating pressure can be calculated using the equation:
(1) P s = BHTP + P fric − P hyd
Ps = surface pressure
BHTP = bottomhole treating pressure
Pfrict = friction pressure
Phyd = hydrostatic pressure
The equation shows that an increase in hydrostatic pressure results in a reduction in surface pressure. This is true as long as any corresponding increases in BHTP and friction pressure remain below the hydrostatic increase. If substantial reductions in surface pressure can be achieved, then frac pack treatments remain a safe and viable option in deepwater and ultra-deepwater environments.
As of October 2007, sixteen total jobs have been pumped with a weighted frac pack fluid. Of these jobs, eleven treatments have been pumped by Chevron in the deepwater GOM. This paper presents data from these treatments where substantial reductions in surface treating pressures were observed. Also shown is the accuracy to which surface treating pressures with the weighted frac-pack fluid can be predicted.
When Will Low Sulphate Seawater No Longer Be Required on the Tiffany Field?
Authors: Al-Riyami Murshid , Mackay Eric , Deliu Gabriel , Jordan Myles , McElhiney John 
Published: February 2008

Abstract
Injection of sulphate rich seawater into reservoirs with formation brines rich in calcium, barium or strontium may result in the precipitation of sulphate scales. One technique for managing mineral scales in fields where scale inhibitor squeeze treatments may prove very difficult or ineffective is injection of low sulphate seawater. The CNR operated Tiffany field in the North Sea is one of the oilfields that has been swept with low sulphate seawater for the longest period (&gt; 10 years) and from the start of water injection, and consequently yields useful information on brine mixing and brine-rock interactions during low sulphate seawater sweep. This paper presents the evolution of individual well brine chemistry data, backed up by reservoir simulation and reactive transport flow modelling, which demonstrates the effect that low sulphate seawater injection has had on the produced brine chemistry. The main impact is that scale inhibitor squeezes have only been required for carbonate scales.
The modelling has been extended to predict future individual well brine compositions to identify potential barium and sulphate concentrations to end of field life, and hence identify any remaining potential barium sulphate scaling risk. However, the predictive modelling has also been used to study the sensitivity to timing of a switch from desulphated to full sulphate seawater injection towards the end of field life, to address the question of when will low sulphate seawater no longer be required on the Tiffany field? This study has significant implications for other basins around the world where desulphation projects are about to commence (Brazil and Angola).
Inhibition Mechanisms for Sulphide Scales
Authors: Okocha C. , Sorbie K. S. , Boak L. S. 
Published: February 2008

Abstract
Sulphide scales have over recent years become increasingly common in many oil and gas producing regions. The main sulphide scales are iron, zinc and lead, with the latter two often occurring together. This paper presents experimental results from a series of static iron sulphide (FeS) inhibition efficiency tests using 2 scale inhibitors (SI), a phosphonate and a polymer. The paper also highlights the methodology which has been developed for assessing iron sulphide scale inhibition. The objective of this preliminary iron sulphide inhibition efficiency study was (a) to establish which of the conventional SI tested inhibit FeS and under which test conditions; (b) to determine the mechanisms through which SIs inhibit FeS; and (c) to determine if it is possible to determine a "minimum inhibitor concentration" (MIC) with this methodology. This preliminary study shows that: (i) The conventional SIs tested in this study do inhibit FeS scale formation; (ii) A clarification phenomenon was observed after sulphide formation using conventional phosphonate which has not been observed/reported previously. This involves the formation of black FeS and the clarification that follows after 24hrs, which indicates subsequent "inhibition", although probably by direct chelation rather than by threshold (sub-stoichiometric) inhibition; (iii) It is possible to obtain an "MIC" from the static bottle test.
Modeling of Three-Phase Flow in the Annuli During Directional UBD Operations
Authors: Mousavi Hasan , Mostafavi Vahidreza , Nazari Tahmineh , Hareland Geir , Shirkavand Farid 
Published: February 2008

Abstract
Underbalanced drilling (UBD) has several advantages compared to conventional drilling. These advantages include the elimination of formation damage, higher penetration rate, reducing circulation loss and the possibility of actually producing hydrocarbons during the drilling process. UBD technology and applications have recently been applied while drilling challenging wells in Iranian fields.
It is generally accepted that the success of underbalanced drilling is dependant on maintaining the wellbore pressure in an operational window determined by the formation pressure, wellbore stability, and the capacity of the surface equipment.
There are several models which can predict the wellbore pressure. Traditional models are mostly empirical and lead to acceptable results for specific conditions but fail for other conditions.
In the last decade of the last century, some mechanistic models have been developed which result in an acceptable range of outcomes for a wide variety of reservoirs.
On the other hand due to the dynamic nature of the process, some researchers have recently focused on development of dynamic models.
This paper presents an improved, comprehensive, mechanistic model for pressure prediction through a well during UBD operations. The comprehensive model consists of a set of correlations for predicting flow pattern and estimating the pressure in addition to two-phase flow parameters in bubble, dispersed bubble, and slug flow. On the other hand the most recently developed empirical correlations have been applied to determine PVT properties. The accuracy of these correlations has been tested in more than 20 oil wells in Iran. Naseri et al. and Almarhoun correlations was applied to determine the live and dead oil viscosities. Naseri et al. model which was originally developed for Iranian reservoirs was used in our model and the results are promising.
Austria’s Path Toward Nationwide Electronic Health Records
Authors: Duftschmid G. , Gerhold L. , Gall W. , Gambal J. , Dorda W. 
Published: February 2008

Summary

Objectives:
This article discusses current planning activities in Austria after legislation has been passed to introduce the electronic health record (EHR).

Methods:
After describing similar activities in several other countries, the authors explore the current situation of healthcare telematics and imminent steps toward the implementation of a lifelong EHR.

Results:
Substantial efforts have been made to coordinate healthcare telematics in Austria since the mid-1990s. One result of these efforts was the definition of a framework for electronic data exchange. A number of standardization projects were also implemented. Major steps have been taken as part of an ongoing healthcare reform to promote the use of healthcare telematics. One important example is a national initiative whose objective is to implement the EHR. This initiative is extensively discussed along with other national activities related to healthcare telematics.

Conclusion:
This EHR initiative has prepared the ground for extensive planning that is currently under way to implement a lifelong EHR in Austria on a national level. Introducing the EHR will have a strong impact on Austrian healthcare and should be performed in concert with international activities. The authors offer a number of practical recommendations for the implementation of an EHR on a national level.
Development of a Telediagnosis Endoscopy System over Secure Internet
Authors: Sakamoto N. , Watanabe M. , Mizushima H. , Tanaka H. , Ohashi K. 
Published: February 2008

Summary

Objectives:
We developed a new telediagnosis system to securely transmit high-quality endoscopic moving images over the Internet in real time. This system would enable collaboration between physicians seeking advice from endoscopists separated by long distances, to facilitate diagnosis.

Methods:
We adapted a new type of digital video streaming system (DVTS) to our teleendoscopic diagnosis system. To investigate its feasibility, we conducted a two-step experiment. A basic experiment was first conducted to transmit endoscopic video images between hospitals using a plain DVTS. After investigating the practical usability, we incorporated a secure and reliable communication function into the system, by equipping DVTS with “TCP2”, a new security technology that establishes secure communication in the transport layer. The second experiment involved international transmission of teleendoscopic image between Hawaii and Japan using the improved system.

Results:
In both the experiments, no serious transmission delay was observed to disturb physicians’ communications and, after subjective evaluation by endoscopists, the diagnostic qualities of the images were found to be adequate. Moreover, the second experiment showed that “TCP2-equipped DVTS” successfully executed high-quality secure image transmission over a long distance network.

Conclusions:
We conclude that DVTS technology would be promising for teleendoscopic diagnosis. It was also shown that a high quality, secure teleendoscopic diagnosis system can be developed by equipping DVTS with TCP2.
Preoperative Circulating Tumor HPV DNA and Oropharyngeal Squamous Cell Disease
Authors: Lam Doreen , Sangal Neel R. , Aggarwal Ashna , Rajasekaran Karthik , Cannady Steven B. , Basu Devraj , Chalian Ara , Weinstein Gregory , Brody Robert M. 
Published: April 2024

ImportanceThe utility of preoperative circulating tumor tissue-modified viral human papillomavirus DNA (TTMV-HPV DNA) levels in predicting human papillomavirus (HPV)–associated oropharyngeal squamous cell carcinoma (HPV+ OPSCC) disease burden is unknown.ObjectiveTo determine if preoperative circulating tumor HPV DNA (ctHPVDNA) is associated with disease burden in patients with HPV+ OPSCC who have undergone transoral robotic surgery (TORS).Design, Setting, and ParticipantsThis cross-sectional study comprised patients with HPV+ OPSCC who underwent primary TORS between September 2021 and April 2023 at one tertiary academic institution. Patients with treatment-naive HPV+ OPSCC (p16-positive) and preoperative ctHPVDNA levels were included, and those who underwent neck mass excision before ctHPVDNA collection were excluded.Main Outcomes and MeasuresThe main outcome was the association of increasing preoperative ctHPVDNA levels with tumor size and lymph node involvement in surgical pathology. The secondary outcome was the association between preoperative ctHPVDNA levels and adverse pathology, which included lymphovascular invasion, perineural invasion, or extranodal extension.ResultsA total of 70 patients were included in the study (65 men [93%]; mean [SD] age, 61 [8] years). Baseline ctHPVDNA levels ranged from 0 fragments/milliliter of plasma (frag/mL) to 49 452 frag/mL (median [IQR], 272 [30-811] frag/mL). Overall, 58 patients (83%) had positive results for ctHPVDNA, 1 (1.4%) had indeterminate results, and 11 (15.6%) had negative results. The sensitivity of detectable ctHPVDNA for identifying patients with pathology-confirmed HPV+ OPSCC was 84%. Twenty-seven patients (39%) had pathologic tumor (pT) staging of pT0 or pT1, 34 (49%) had pT2 staging, and 9 patients (13%) had pT3 or pT4 staging. No clinically meaningful difference between detectable and undetectable preoperative ctHPVDNA cohorts was found for tumor size or adverse pathology. Although the median preoperative ctHPVDNA appeared to be higher in pT2 through pT4 stages and pN1 or pN2 stages, effect sizes were small (pT stage: η2, 0.002 [95% CI, −1.188 to 0.827]; pN stage: η2, 0.043 [95% CI, −0.188 to 2.600]). Median preoperative log(TTMV-HPV DNA) was higher in active smokers (8.79 [95% CI, 3.55-5.76]), compared with never smokers (5.92 [95% CI, −0.97 to 1.81]) and former smokers (4.99 [95% CI, 0.92-6.23]). Regression analysis did not show an association between tumor dimension or metastatic lymph node deposit size and preoperative log(TTMV-HPV DNA). After univariate analysis, no association was found between higher log(TTMV-HPV DNA) levels and adverse pathology.Conclusions and RelevanceIn this cross-sectional study, preoperative ctHPVDNA levels were not associated with disease burden in patients with HPV+ OPSCC who underwent TORS.
Single‐Atom Nanozyme‐Like Lanthanum Moieties for High‐Performance Electromagnetic Energy Absorption
Authors: Shi Yanan , Ma Ziqian , Zhang Xiao , Ma Zheng , Yan Feng , Zhu Chunling , Chen Yujin 
Published: April 2024

AbstractSingle‐atom (SA) nanozymes have unprecedented physicochemical performance due to their integrated merits of both atomically dispersed metal atoms and bio‐enzymes. However, the structure‐function relationship between the SA nanozyme‐like structure and its dielectric performance is still unclear. Furthermore, controllable synthesis of SA nanozyme‐like structures remains challenging due to their unique five‐coordinated configurations. Here, a dicyandiamide‐mediated pyrolysis strategy is proposed to anchor five nitrogen‐coordinated lanthanum (La)–N5 moieties on interconnected N‐doped graphene nanocages (La‐N5/ING). Theoretical predictions indicate that the spatially coordinated La–N5 moieties exhibit significantly enhanced conduction loss and polarization loss compared to La–N4 moieties, as evidenced by the experimental results. Moreover, the polydimethylsiloxane‐coated chemically cross‐linked film constructed by the La‐N5/ING and aramid nanofibers has outstanding electromagnetic wave (EMW) absorption performance with an effective absorption bandwidth (EAB10) of 6.24 GHz at a thickness of merely 2.0 mm, outperforming those of most reported carbon‐based films. Importantly, the film also has excellent flexibility, hydrophobicity, mechanical strength, and structural stability, ensuring its application potential in practical environments. These findings provide crucial insights into the microscopic environment of SA on the dielectric properties of their host materials, and a critical method for the preparation of multifunctional films with spatial coordinated SA.
All‐Polarized Elastic Wave Attenuation and Harvesting via Chiral Mechanical Metamaterials
Authors: Park Jeonghoon , Lee Geon , Kwon Hyunhee , Kim Miso , Rho Junsuk 
Published: April 2024

AbstractManipulating elastic waves of all polarizations is highly challenging due to the complex behavior of elastic waves. To achieve simultaneous broadband vibration attenuation and energy harvesting across all polarizations of elastic waves at low‐frequency ranges, a chiral mechanical metamaterial‐based energy harvester is proposed in this study. The systematic development of a complete bandgap and defect structure is achieved through theoretical eigenfrequency analysis and numerical simulations. The defect structure is incorporated to induce defect modes for all wave polarizations within the complete bandgap region, ensuring their compatibility with the overall shape of the structure. The proposed chiral mechanical metamaterial with defect (CMMD) demonstrated significant performance improvements, achieving electrical output power enhancements that are 20.5 times for flexural waves and 511.4 times for longitudinal‐torsional waves compared to the defectless chiral mechanical metamaterial. This study accentuates the thoughtful design and multifaceted utility of chiral mechanical metamaterials, paving the way for their application not only in energy harvesting but also in wave attenuation for various polarizations.
Recent Advances in Radical Transformations of Propargylic Alcohols
Authors: Liang Meng , Ma Haojie , Song Xian‐Rong , Xiao Qiang 
Published: April 2024

AbstractPropargylic alcohols are regarded as a class of readily available and versatile synthons in organic synthesis. Due to their unique bifunctional character, the transformation of propargylic alcohols has been widely utilized as a powerful strategy for the construction of various functionalized frameworks over the past few decades. Recently, the radical transformation of propargylic alcohols has attracted considerable attention in synthetic chemistry. This review summarizes recent progress in the radical transformation of propargylic alcohols. Based on the different mechanisms of radical formation underlying these transformations, this review has been divided into four parts: (1) transition‐metal catalyzed radical transformation; (2) photo‐induced radical transformation; (3) electro‐induced radical transformation; and (4) metal‐free or oxidant‐mediated radical transformation of propargylic alcohols.
Silicon Vacancies Diamond/Silk/PVA Hierarchical Physical Unclonable Functions for Multi‐Level Encryption
Authors: Jiao Fuhang , Lin Chaonan , Dong Lin , Mao Xin , Wu Yi , Dong Fuying , Zhang Zhenfeng , Sun Junlu , Li Shunfang , Yang Xun , Liu Kaikai , Wang Lijun , Shan Chong‐Xin 
Published: April 2024

AbstractPhysical unclonable functions (PUFs) have emerged as a promising encryption technology, utilizing intrinsic physical identifiers that offer enhanced security and tamper resistance. Multi‐level PUFs boost system complexity, thereby improving system reliability and fault tolerance. However, crosstalk‐free multi‐level PUFs remain a persistent challenge. In this study, a hierarchical PUF system that harnesses the spontaneous phase separation of silk fibroin /PVA blend and the random distribution of silicon‐vacancy diamonds within the blend is presented. The thermodynamic instability of phase separation and inherent unpredictability of diamond dispersion gives rise to intricate random patterns at two distinct scales, enabling time‐efficient hierarchical authentication for cryptographic keys. These patterns are complementary yet independent, inherently resistant to replication and damage thus affording robust security and reliability to the proposed system. Furthermore, customized authentication algorithms are constructed: visual PUFs authentication utilizes neural network combined structural similarity index measure, while spectral PUFs authentication employs Hamming distance and cross‐correlation bit operation. This hierarchical PUF system attains a high recognition rate without interscale crosstalk. Additionally, the coding capacity is exponentially enhanced using M‐ary encoding to reinforce multi‐level encryption. Hierarchical PUFs hold significant potential for immediate application, offering unprecedented data protection and cryptographic key authentication capabilities.
Tailoring the Chemical/Electrochemical Response in a Quasi−Solid Polymer Electrolyte Enables the Simultaneous In Situ Construction of Superior Cathodic and Anodic Interfaces
Authors: Zhao Chenying , Lu Yun , Yan Kang , Guan Yibiao , Jiang Shixiong , Wang Jiayang , Guo Shiyuan , Cao Mingxuan , Li Ning , Su Yuefeng , Wu Feng , Chen Lai 
Published: April 2024

AbstractAlthough the flexibility of the quasi−solid polymer electrolyte favors its surface conformal to the electrode, interfacial damage originating from side reactions between the electrolyte and the electrode remains dominant for battery failure. The design of quasi−solid electrolytes compatible with both aggressive nickel−rich cathode and lithium metal anode persists critical to the application of quasi−solid high−voltage lithium metal batteries (LMBs). Herein, a chemical/electrochemical response strategy is proposed to construct simultaneously stable cathodic and anodic interfaces relying on the synergistic effect of 1,4,7,10,13,16−hexaoxacyclooctadecane (18C6) and LiNO3. The distinctive [18C6Li]+NO3− cluster modifies electric double layer structure by specific adsorption on the electrode, thereby regulating the interfacial layer composition and construction. The NO3− on electrode preferentially decomposes to improve the interfacial performances, leaving the [18C6Li]+ to cut off the side reaction. Furthermore, the 18C6 coordinates with detrimental transition metal ions from NMC811 cathode and converts into useful clusters alleviating the knock−on effect. Thus, the quasi−solid electrolyte with 18C6 and LiNO3 enables Li||NMC811 coin cell to cycle stably over wide operation temperature (0−55 °C), especially, achieving high capacity retention of 79.2% after 300 cycles at 30 °C. This chemical/electrochemical response strategy projects new insights into the design of smart reactive electrolytes for high−voltage LMBs.
Full‐Dimensional Analysis of Gaseous Products Within Li‐Ion Batteries by On‐Line GC‐BID/MS
Authors: Zhang Haitang , Wu Xiaohong , Li Zhengang , Zou Yeguo , Wang Junhao , Yu Xiaoyu , Chen Jianken , Xue Jiyuan , Zhang Baodan , Tian Jing‐Hua , Hong Yu‐hao , Qiao Yu , Sun Shi‐Gang 
Published: April 2024

AbstractThe gas release within Li‐ion batteries, particularly during cycling and storage, can result in rapid performance degradation and potential safety hazards. However, this area has not garnered sufficient attention until now, primarily because the gassing information collected by typical OEMS/DEMS is quite limited and even inaccurate. Herein, for the first time, a state‐of‐the‐art on‐line GC‐BID/MS to full‐dimensionally analyze the gassing behavior within both lab‐scale coin‐type cell (in situ mode) and industry‐scale pouch‐type cell (operando mode) is originally designed/constructed. Not limited to common permanent gases (e.g. H2, CO, etc.) detected by online GC‐BID, but also complicated/various (semi‐)volatile products are identified/quantified by online GC‐MS. Based on the real‐time evolution information of water, alcohols, aldehydes, ethers, esters, and hydrocarbons, the decomposition mechanisms of electrolyte on both graphite anode and/or LCO cathode sides is further supplemented/perfected. Moreover, at the level of the device, series derivative/crosstalk reactions induced by trapped/accumulated gaseous species are unveiled in practical pouch‐cell.