bluuebunny/crossref_metadata_2025 huggingface dataset:
Life of Alexander von Humboldt
Authors: Löwenberg Julius , Avé-Lallemant Robert , Dove Alfred
Published: December 2012

Alexander von Humboldt (1769–1859) was a naturalist, explorer and philanthropist now well known for his multidisciplinary approach to science. First published in English in 1873, this two-volume biography was translated from the German edition of 1872, edited by Karl Bruhns, which had been compiled in commemoration of the centenary of Humboldt's birth. Incorporating numerous extracts of Humboldt's own warmly written letters and anecdotes from his many acquaintances, it charts his travels in South America, Asia and Europe. Volume 2 covers his later life, exploring his impecunious period in Paris at the École Polytechnique, where he shared rooms with the famous French chemist Gay-Lussac, and later, his close association with King Frederick William IV of Prussia. Ideal for students and researchers in the history of science, this is a minutely detailed and compelling insight into the life of the man behind the scientist.
Notes on the Natural History of the Strait of Magellan and West Coast of Patagonia
Authors: Cunningham Robert O.
Published: December 2012

The Scottish naturalist Robert O. Cunningham (1841–1918) began his 1866 voyage to South America in inclement weather, and, by the eleventh day of travel, noted a 'pond' forming in his tiny cabin aboard HMS Nassau. With never-failing humour, Cunningham presents here a record of the zoological, botanical and geological observations made across the three years he spent at sea. As the ship's naturalist (recommended for the post by J. D. Hooker), his time was given wholly to research and exploration, and his findings are both fascinating and thorough. Included are his anecdotal records of seamen's slang, research into the history of the changing landscapes he visited, which had been previously documented by travellers as diverse as Drake and Darwin, statistical data on various species of animals and plants, and twenty-two original images. First published in 1871, this is an absorbing testament of the breadth of the explorer-naturalist's interests.
City Versus Countryside in Mao's China
Authors: Brown Jeremy
Published: December 2012

The gap between those living in the city and those in the countryside remains one of China's most intractable problems. As this powerful work of grassroots history argues, the origins of China's rural-urban divide can be traced back to the Mao Zedong era. While Mao pledged to remove the gap between the city worker and the peasant, his revolutionary policies misfired and ended up provoking still greater discrepancies between town and country, usually to the disadvantage of villagers. Through archival sources, personal diaries, untapped government dossiers and interviews with people from cities and villages in northern China, the book recounts their personal experiences, showing how they retaliated against the daily restrictions imposed on them while traversing between the city and the countryside. Vivid and harrowing accounts of forced and illicit migration, the staggering inequity of the Great Leap Famine and political exile during the Cultural Revolution reveal how Chinese people fought back against policies that pitted city dwellers against villagers.
Georgii Pachymeris de Michaele et Andronico Palaeologis libri tredecim
Authors: Pachymeres George
Published: December 2012

This history of the reigns of the first two emperors of the Palaiologos Dynasty by George Pachymeres (1242–1310) was edited by the German scholar Immanuel Bekker (1785–1871) on the basis of the work of the French Jesuit, Pierre Poussines (1609–86), and published in two volumes in 1835. The family of Pachymeres had fled to the neighbouring empire of Nicaea (Iznik) after the capture of Constantinople by the Franks in 1204. Michael Palaiologos (1223–82) became leader of the armies in Nicaea in 1259; two years later he had driven the Latins from Constantinople and was crowned Emperor Michael VIII, with his two-year-old son Andronikos (1259–1332) as his co-ruler and heir. Pachymeres also wrote on topics such as music and philosophy, but is best remembered for this history of his own times. Volume 2 describes the life and reign of Andronikos Palaiologos up to 1308.
Nicephori Gregorae Byzantina historia
Authors: Gregoras Nicephorus
Published: December 2012

This three-volume edition of the History by Nicephorus Gregoras (c. 1295–1360) was edited by Ludwig Schopen (Volumes 1 and 2, 1829–30) and Immanuel Bekker (Volume 3, 1855). The astronomer and historian, Gregpras, became the archivist of the Byzantine Emperor Andronikos II Palaiologos (to whom he proposed a calendar reform similar to that adopted by Pope Gregory XIII in 1582), and was involved in the fruitless negotiations of 1333 to unite the Greek and Latin Churches. The thirty-seven books of Gregoras' History overlap with the work by George Pachymeres, and continue the narrative to 1359. This period is also covered in the History by the ex-Emperor John Cantacuzene, and both these authors are also reissued in this series. The Latin introduction to Volume 1 includes a life and bibliography of Gregoras, and the Greek text (with Latin translation) begins with the capture of Constantinople by the Franks in 1204.
Ioannis Cantacuzeni Eximperatoris historiarum Libri IV
Authors: Cantacuzenus Ioannes
Published: December 2012

This three-volume work of Byzantine history by the ex-Emperor John VI Cantacuzene was edited, together with a Latin translation by the Jesuit scholar, Pontanus (1542–1626), by Ludwig Schopen (1799–1867), and published between 1828 and 1832. It covers part of the same period as the works by George Pachymeres and Nicephorus Gregoras (also reissued in this series) and the three accounts can usefully be compared. John Cantacuzene (c. 1292–1383) was unusual among Byzantine emperors in that he appears to have been reluctant to take the throne, and also in that, having been deposed in 1354, he was allowed to retire to a monastery, where he wrote this account of his times. The historian Edward Gibbon, among others, noted the self-justificatory tone of his memoir. Volume 1 includes the life of John by Pontanus, and covers the period from 1321 to the death of Andronikos III in 1341.
The Croker Papers
Authors: Croker John Wilson
Published: December 2012

John Wilson Croker (1780–1857), politician and writer, was educated at Trinity College, Dublin, and studied for the bar before moving to London. He was appointed as Deputy Chief Secretary for Ireland when Sir Arthur Wellesley took command of the Army in Portugal, and subsequently became Secretary to the Admiralty, an important role in wartime. He was noted for his efficiency and honesty, and held the post until 1830, despite changes of government. He was a prolific letter-writer, on both professional and personal matters, and almost all his correspondents were men of importance in their field. This three-volume edition of his papers was published in 1884. Volume 1 covers Croker's early life and career until 1828. He had many friends, although as a harsh literary critic he also made enemies. He gives amusing anecdotes of Regency society and royalty, but suffered personal tragedy with the death of his son.
The Croker Papers
Authors: Croker John Wilson
Published: December 2012

John Wilson Croker (1780–1857), politician and writer, was educated at Trinity College, Dublin, and studied for the bar before moving to London. He was appointed as Deputy Chief Secretary for Ireland when Sir Arthur Wellesley took command of the Army in Portugal, and subsequently became Secretary to the Admiralty, an important role in wartime. He was noted for his efficiency and honesty, and held the post until 1830, despite changes of government. He was a prolific letter-writer, on both professional and personal matters, and almost all his correspondents were men of importance in their field. This three-volume edition of his papers was published in 1884. Volume 2 covers the period 1829–42. Catholic emancipation and parliamentary reform dominated the political agenda in the earlier years, while the years 1841–2 were notable for the cause célèbre regarding the Marquess of Hertford's will, which, perhaps unfairly, damaged Croker's reputation.
The Croker Papers
Authors: Croker John Wilson
Published: December 2012

John Wilson Croker (1780–1857), politician and writer, was educated at Trinity College, Dublin, and studied for the bar before moving to London. He was appointed as Deputy Chief Secretary for Ireland when Sir Arthur Wellesley took command of the Army in Portugal, and subsequently became Secretary to the Admiralty, an important role in wartime. He was noted for his efficiency and honesty, and held the post until 1830, despite changes of government. He was a prolific letter-writer, on both professional and personal matters, and almost all his correspondents were men of importance in their field. This three-volume edition of his papers was published in 1884. Volume 3 covers the period from 1843 until Croker's death. It includes the Corn Law debates, the Irish Famine, and correspondence with the Duke of Wellington. Croker remained an active literary critic for the Quarterly Review, which made him enemies who damaged his posthumous reputation.
The Story of the ‘Domus Dei' of Portsmouth
Authors: Wright Henry Press
Published: December 2012

The 'Domus Dei', otherwise known as the Garrison Church, in Portsmouth is a familiar landmark to ships sailing into and out of Portsmouth Harbour. It was originally founded about 1210 as a 'hospital' for travellers - especially pilgrims - arriving at the port. After the Reformation its main building became a church, and was frequently used by naval and army personnel before embarkation. In 1814 the sovereigns and leaders of the Allies against Napoleon gathered there during the peace celebrations following his abdication, but by the middle of the century it had become dilapidated. A restoration project was begun in 1865, and this history of the building was published in 1873 by Henry P. Wright, 'chaplain to the Forces', with the intention of raising further donations towards the refurbishment, which he describes in detail. The church was severely damaged by bombing in 1941, but remains consecrated and is occasionally used for services.
The War, from the Landing at Gallipoli to the Death of Lord Raglan
Authors: Russell William Howard
Published: December 2012

The journalist William Howard Russell (1820–1907) is sometimes regarded as being the first war correspondent, and his reports from the conflict in the Crimea are also credited with being a cause of reforms made to the British military system. Published in 1855, during the late stages of the conflict, this is a collection of eye-witness reports originally printed in The Times newspaper, including the famous account, from 25 October 1854, of the Charge of the Light Brigade during the Battle of Balaclava, and the other engagement on the same day which gave rise to the phrase 'the thin red line'. Russell's accounts are unflinching in their dramatic descriptions of the appalling and insanitary conditions endured by the ill-provisioned troops, and his criticism of those in command, particularly Lord Raglan, had a dramatic impact on the British people and government. Reading these letters today, it is easy to understand why.
The Personal Adventures and Experiences of a Magistrate during the Rise, Progress, and Suppression of the Indian Mutiny
Authors: Thornhill Mark
Published: December 2012

In 1857, when the Indian Mutiny broke out, Mark Thornhill (1822–1900) was the magistrate of Muttra, modern Mathura. His vivid account of ensuing events - published in 1884 - including a night ride to Agra through the rebel army and the developing tensions inside the fort, was well reviewed at the time, and, more recently, became one of the sources for J. G. Farrell's The Siege of Krishnapur. Also including excursuses on the history and architecture of Agra from the time of Babur, and ghost stories pertaining to it - Thornhill published a separate volume of Indian fairy tales - the narrative is notably modern in its acute psychological perceptions of response to violence and its conservationist concern for damage to buildings. Thornhill wrote the book as an historical analysis, and his conclusions about the underlying causes of the Mutiny illuminate subsequent developments in the region as well as the conflict he describes.
Lord Amherst and the British Advance Eastwards to Burma
Authors: Ritchie Anne Thackeray , Evans Richardson
Published: December 2012

In 1823, after relatively undistinguished diplomatic missions to Sicily and China, Lord Amherst (1773–1857) was appointed Governor-general of Bengal, a compromise candidate following Canning's sudden withdrawal to become foreign secretary. Arriving in India, he found the country on the brink of war with Burma, which he was unable to prevent or quickly to resolve, resulting in an expensive and demoralising two-year campaign, and the death of his eldest son. This 1894 biography, written by Anne Thackeray Ritchie (1837–1919), elder daughter of the novelist, and journalist Richardson Evans (1846–1923), was part of a series established by Sir William Wilson Hunter (1840–1900), a former Administrator in the subcontinent. Decidedly flattering in tone and glossing the War as 'a glorious enterprise of arms', this book, which quotes extensively from Lady Amherst's diary and other contemporary sources, is a fascinating example of the late-Victorian presentation of earlier colonial administration.
Imperial Defence
Authors: Dilke Charles Wentworth , Wilkinson Spenser
Published: December 2012

The liberal Radical MP Sir Charles Wentworth Dilke (1843–1911) campaigned for (among many other causes) votes for women and labourers, legalisation of trade unions and universal education. His republican sentiments damaged his political reputation, and earned him the hostility of Queen Victoria. However, despite his views on the monarchy he was an imperialist, and his early work, Greater Britain (1868; also available in this series), was widely read. In the 1890s he became known as a parliamentary expert on military, colonial and foreign affairs. This 1892 work, co-written with Spenser Wilkinson (1853–1937), a journalist and military historian, together with Dilke's earlier work, Problems of Greater Britain, led to the founding of a parliamentary committee on imperial defence. The book argues that, while hoping to avert war by diplomacy, the Government has a duty to maintain a naval and military force to protect the interests of its citizens.
Treatise on Naval Courts Martial
Authors: Delafons John
Published: December 2012

Originally published in 1792, this work was revised (incorporating new material) and corrected for the 1805 edition, reissued here. As a ship's purser and occasional Judge Advocate, Delafons had considerable experience of advising in naval courts martial, including first-hand involvement for the defence in the trial of Peter Heywood, a midshipman on board HMS Bounty during the mutiny of 1789. He intended this work to be a textbook for conducting judicial proceedings in the Royal Navy, and it is also now a fundamental text for historians and researchers in both the legal and naval history of a period of British maritime supremacy. Delafons covers the subjects of jurisdiction, evidence, sentencing, and the roles of individuals within the trial. He also makes a comparison between the law of the Navy and its practical applications and that of the civil courts, and examines the development of the Naval Code itself.
Autobiography of Miss Cornelia Knight
Authors: Knight Ellis Cornelia
Published: December 2012

This two-volume Autobiography by Cornelia Knight (1757–1837) was published in 1861. It was complied by the military historian Sir John Kaye from her journals and a memoir based on them, written late in life and remaining incomplete at her death. Cornelia Knight, the daughter of an admiral, was highly educated: she knew ten languages, was skilled at painting and drawing, and published novels and poetry. In 1813 she was appointed to the household of Princess Charlotte of Wales. In 1814, the Prince Regent dismissed all his daughter's attendants, and Knight returned to a life of literature and European travel. In Volume 2, Knight continues her account of her dismissal, and a later meeting with the Princess, now happily married (though she was shortly to die in childbirth). Knight spent another twenty years in the court circles of Europe: an appendix gives further extracts from her journals and her 'anecdote book'.
Early Years of His Royal Highness the Prince Consort
Authors: Grey Charles
Published: December 2012

Originally written for private circulation among the Royal Family, this book, written by Lieutenant-General Charles Grey (1804–70), was first published in 1867. It details Prince Albert's life from his birth in 1819 through to his wedding to Queen Victoria and the first year of their married life. The Queen commissioned Grey, who had been secretary to both Albert and herself, as her husband's biographer, and the book was granted a wider publication, so that all who read it would 'tend to a better and higher appreciation of Prince Albert's great character'. Sourced from letters and memoranda, the book traces the development of Albert from an intelligent and gentle boy to the intellectual and moral compass of a nation. It records Albert's first visits to England, the wedding, his love for his adopted country and life in London, and includes details such as an attempted assassination of the Queen.
The Life of Sir Anthony Panizzi, K.C.B.
Authors: Fagan Louis
Published: December 2012

Anthony Panizzi (1797–1879), born in Brescello, Italy, qualified as a lawyer, but fled to Switzerland in 1823 to avoid arrest for his political activities in support of Italian unification. He then moved to England, where he became a naturalised British subject. The patronage of Lord Brougham, the Lord Chancellor, got him a post in the British Museum Library, where he remained for thirty-five years. He was responsible for the great expansion of the library, the building of the famous round Reading Room, and the compilation of cataloguing rules which remain influential today. Volume 1 of this two-part 1880 biography by his colleague Louis Fagan (1845–1903) deals with Panizzi's early life in Italy, his arrival in England, his scholarly work as editor of Ariosto and Professor of Italian, and his early years at the British Museum. Panizzi combined his career with continuing support for the cause of Italian unity.
The Creevey Papers
Authors: Creevey Thomas
Published: December 2012

Thomas Creevey (1768–1838) was a Whig politician, diarist and letter-writer, whose papers provide an important source for the history of the early nineteenth century. Although a relatively poor man, he was adept at making friends with important people, and received hospitality and financial help from them. His letters are full of gossip, often indiscreet, giving a vivid picture of the society and politics of the day. They form an interesting comparison with the papers of his contemporaries, J. W. Croker, who as a Tory was in power for most of the period in question, and Charles Greville (both available in this series). Creevey is perhaps best remembered for his description of Brussels during Napoleon's 'Hundred Days'. This two-volume work edited by Sir Herbert Maxwell (1845–1937) was first published in 1903. Volume 2 covers the period 1820–37, and the accession of Victoria, described here as a 'homely little being'.
The History of the Indian Navy (1613–1863)
Authors: Low Charles Rathbone
Published: December 2012

Charles Rathbone Low (1837–1918) was a lieutenant in the Indian Navy and author of popular books on military history and nautical exploration, including Soldiers of the Victorian Age and Maritime Discovery. This two-volume work, first published in 1877, comprehensively covers the history of the British Indian Navy, from its origins as the Bombay Marine to its abolition in 1863. It is an exceptionally detailed historical source, containing indexes of the ships and officers of the Indian Navy, and as such, it is a work of great importance to those interested in the history of the Indian Navy or the people that came into contact with it. Volume 2 begins in 1831 and includes chapters on both the Burmese and Persian Wars. The final chapters detail the Navy's involvement in the Indian Mutiny of 1857 and the events that led to its abolition.
The Rose Book
Authors: Hibberd Shirley
Published: December 2012

James Shirley Hibberd (1825–90) was a journalist and writer on gardening, whose popular works had great influence on middle-class taste. Although not a trained horticulturalist, his many books were based on practical experience. He developed a succession of gardens in North London, concentrating on particular types of plants, and his books reflected this work, with this book of 1864 and The Fern Garden (1869) being particularly successful. He also wrote on garden design, flower arrangement, garden furniture and architecture, and his Rustic Adornments of 1856 (reissued in this series, together with The Fern Garden), is an interesting document of social history. He edited the magazine Floral World until 1875 and later The Gardener's Magazine, and was even consulted by the government about potato blight. His engaging and very personal style made him a popular forerunner of modern celebrity gardeners, and set a fashion for highly decorative and ornamental gardens.
DUNKL–WILLIAMS INEQUALITIES FOR INTEGRABLE FUNCTIONS IN BANACH SPACE
Authors: CAO JIANBING
Published: December 2012

In this paper, a generalisation of the Dunkl–Williams inequality is established for strongly integrable functions with values in a Banach space. Some applications are also presented.
RELAY PLANTING OF WHEAT IN COTTON: AN INNOVATIVE TECHNOLOGY FOR ENHANCING PRODUCTIVITY AND PROFITABILITY OF WHEAT IN COTTON–WHEAT PRODUCTION SYSTEM OF SOUTH ASIA
Authors: BUTTAR G. S. , SIDHU H. S. , SINGH VICKY , JAT M. L. , GUPTA R. , SINGH YADVINDER , SINGH BALDEV
Published: December 2012

Cotton–wheat (CW) is the second most important cropping system after rice–wheat in South Asia. Sowing of wheat after cotton is usually delayed due to late pickings coupled with time needed for seedbed preparation, resulting in low wheat yield. Lack of suitable machinery is a major constraint to direct drilling of wheat into the heavy cotton stubbles. An innovative approach with much promise is the ‘2-wheel tractor-based self-propelled relay seeder’ with seed-cum-fertilizer attachment. On-farm trials were conducted at four locations during 2009–2010 and at 10 locations during 2010–2011 to evaluate the following four wheat establishment methods in CW-dominated areas of south-western Punjab, India: (1) zero till seeding in standing cotton using a self-propelled relay seeder, (2) relay seeding in standing cotton with a manual drill without prior tillage (2010 only), (3) relay broadcast seeding in standing cotton following light manual tillage and (4) conventional sowing of wheat after cotton harvest (conventional tillage and sowing with a seed–fertilizer drill). Planting of wheat under conventional practice was delayed by 20–44 days compared with relay seeding. Seed cotton yield was also significantly higher with relay seeding due to opportunity for one additional picking. Yield of wheat sown with the self-propelled relay seeder was 41.2% and 11.8% higher than with conventional practice in 2009–2010 and 2010–2011 respectively. The increase in wheat yield under relay seeding of wheat was primarily due to higher spike density and more grains per spike. The net income from the CW system was 28.2% higher for the self-propelled relay seeder than with conventional sowing.
FARM-LEVEL ECONOMIC IMPACTS OF CONSERVATION AGRICULTURE IN ECUADOR
Authors: NGUEMA ABIGAIL , NORTON GEORGE W. , ALWANG JEFFREY , TAYLOR DANIEL B. , BARRERA VICTOR , BERTELSEN MICHAEL
Published: December 2012

Farm households in the Andean region of South America face serious livelihood challenges, including a poor natural resource base and declining agricultural yields. Conservation agriculture has been identified as a potential solution to environmental degradation and the associated poverty and food insecurity in the region. This study analyses the potential economic impact of conservation agriculture in two sub-watersheds in central Ecuador utilizing a linear programming model and data from experiments in farmer fields. The model found that specific cover crops, crop rotations and reduced tillage designed to reduce soil erosion and increase soil organic matter can lead to increased incomes for farm households in a time period of as short as two years. It appears that conservation agriculture practices have the potential to improve the livelihoods of the rural poor in Ecuador because conservation agriculture activities entered the revenue-maximizing model solution for both sub-watersheds.
Growth of amorphous carbon and graphene on pulse laser deposited SiC films and their characterization studies
Authors: Mishra Pratima K. , Sahoo Bijayalaxmi
Published: December 2012

Laser induced ablation studies have been carried out on formation of amorphous carbon and graphene on SiC thin films with their detailed characterization studies. Pulse laser ablation technique with process parameters such as 248 nm KrF excimer laser, frequency 10 Hz, 200 mJ of laser energy, and chamber pressure of 7 × 10−6 mbar has been used. Films were characterized in detail by grazing incidence X-ray diffraction, Fourier transform infrared, micro-Raman, X-ray reflectivity, Field emission scanning electron microscopic, transmission electron microscope, and Nano-indentation techniques and the results are reported. As deposited SiC film surface is rich in amorphous carbon and the same has been used as the nucleation site for further growth of graphene on SiC films. Film hardness increased from 29 GPa to 37 GPa for SiC film and graphene on SiC film (C-SiC), respectively. These films show bands due to surface phonon polariton mode in the range of 810–840 cm−1 that is a research concern today in nano-photonics area. Further these materials find applications in understanding the laser irradiation effects on SiC based nuclear fusion wall material.
Using morphemes in language modeling and automatic speech recognition of Amharic
Authors: TACHBELIE MARTHA YIFIRU , ABATE SOLOMON TEFERRA , MENZEL WOLFGANG
Published: December 2012

This paper presents morpheme-based language models developed for Amharic (a morphologically rich Semitic language) and their application to a speech recognition task. A substantial reduction in the out of vocabulary rate has been observed as a result of using subwords or morphemes. Thus a severe problem of morphologically rich languages has been addressed. Moreover, lower perplexity values have been obtained with morpheme-based language models than with word-based models. However, when comparing the quality based on the probability assigned to the test sets, word-based models seem to fare better. We have studied the utility of morpheme-based language models in speech recognition systems and found that the performance of a relatively small vocabulary (5k) speech recognition system improved significantly as a result of using morphemes as language modeling and dictionary units. However, as the size of the vocabulary increases (20k or more) the morpheme-based systems suffer from acoustic confusability and did not achieve a significant improvement over a word-based system with an equivalent vocabulary size even with the use of higher order (quadrogram) n-gram language models.
Gender and Legislative Preferences: Evidence from the Argentine
Provinces
Authors: Barnes Tiffany D.
Published: December 2012

Women are underrepresented in most of the world's legislatures. While
the scarcity of female representation is problematic for multiple reasons,
one of the central concerns of advocates and scholars rests on the
assumption that women have different legislative preferences than their male
counterparts. If this is the case, then it implies that where women do not
occupy an equitable proportion of the legislature, their interests are not
well represented.
On Substantive Representation, Diversity, and Responsiveness
Authors: Celis Karen
Published: December 2012

When are “the people”—with all its different groups—represented? It is
commonly accepted that democratic representation implies that no significant
parts of the population are excluded from the right to vote or to stand for
election and, similarly, that parliaments and even governments should, to a
certain extent, mirror the represented and governed population. If
authorization and accountability indicate the democratic quality of the
formal dimension of representation (i.e., it is democratic when it is
accountable), then representativeness allows for evaluating descriptive
representation (i.e., it is democratic when it is representative of society)
(see also Celis 2009). But what are our standards for judging the democratic
quality of substantive representation? According to Hanna F. Pitkin, that
normative standard is the representative's responsiveness: substantive
representation is “acting in the interest of the represented,
in a manner responsive to them.”
Responsiveness turns what representatives do into substantive representation
of the demos. It is a metacriterion for
democratic representation in the sense that accountability and descriptive
representativeness need also to ensure responsiveness. But, again, questions
arise: How should we understand responsiveness? How do representatives
establish it? Where and when does responsiveness need to be
established?
Quantifying uncertainty sources in an ensemble of hydrological climate‐impact projections
Authors: Bosshard T. , Carambia M. , Goergen K. , Kotlarski S. , Krahe P. , Zappa M. , Schär C.
Published: December 2012

Key Points

ANOVA method applied to climate‐impact modeling

Detailed assessment of changes in water balance quantities due to climate change

Interactions of uncertainty sources
A regression modeling approach for studying carbonate system variability in the northern Gulf of Alaska
Authors: Evans Wiley , Mathis Jeremy T. , Winsor Peter , Statscewich Hank , Whitledge Terry E.
Published: December 2012

The northern Gulf of Alaska (GOA) shelf experiences carbonate system variability on seasonal and annual time scales, but little information exists to resolve higher frequency variability in this region. To resolve this variability using platforms‐of‐opportunity, we present multiple linear regression (MLR) models constructed from hydrographic data collected along the Northeast Pacific Global Ocean Ecosystems Dynamics (GLOBEC) Seward Line. The empirical algorithms predict dissolved inorganic carbon (DIC) and total alkalinity (TA) using observations of nitrate (NO3−), temperature, salinity and pressure from the surface to 500 m, with R2s > 0.97 and RMSE values of 11 µmol kg−1 for DIC and 9 µmol kg−1 for TA. We applied these relationships to high‐resolution NO3− data sets collected during a novel 20 h glider flight and a GLOBEC mesoscale SeaSoar survey. Results from the glider flight demonstrated time/space along‐isopycnal variability of aragonite saturations (Ωarag) associated with a dicothermal layer (a cold near‐surface layer found in high latitude oceans) that rivaled changes seen vertically through the thermocline. The SeaSoar survey captured the uplift to <100 m of dense, high‐pCO2 waters at the shelf break that had been forced by the passage of a Yakutat eddy. During this event, the aragonite saturation horizon (depth where Ωarag = 1) shoaled to a previously unseen depth in the northern GOA. This work is similar to recent studies aimed at predicting the carbonate system in continental margin settings, albeit demonstrates that a NO3−‐based approach can be applied to high‐latitude data collected from platforms capable of high‐frequency measurements.
Increased normal incidence photocurrent in quantum dot infrared photodetectors
Authors: Shao Jiayi , Vandervelde Thomas E. , Barve Ajit , Stintz Andreas , Krishna Sanjay
Published: December 2012

We have increased the ratio of s-polarization (normal incidence) to p-polarization photocurrent to 50% in a quantum dot-in-a-well based infrared photodetector form the typical s-p polarization ratio about 20%. This improvement was achieved by engineering the dot geometry and the quantum confinement via post growth capping materials of the Stranski Krastanov growth mode quantum dots (QDs). The TEM images show that the height to base ratio of shape engineered QDs was increased to 8 nm/12 nm from the control sample's ratio 4 nm/17 nm. The dot geometry correlates with the polarized photocurrent measurements of the detector.
Kuramoto model with coupling through an external medium
Authors: Schwab David J. , Plunk Gabriel G. , Mehta Pankaj
Published: December 2012

Synchronization of coupled oscillators is often described using the Kuramoto model. Here, we study a generalization of the Kuramoto model where oscillators communicate with each other through an external medium. This generalized model exhibits interesting new phenomena such as bistability between synchronization and incoherence and a qualitatively new form of synchronization where the external medium exhibits small-amplitude oscillations. We conclude by discussing the relationship of the model to other variations of the Kuramoto model including the Kuramoto model with a bimodal frequency distribution and the Millennium bridge problem.
Defect mediated reversible ferromagnetism in Co and Mn doped zinc oxide epitaxial films
Authors: Mal Siddhartha , Nori Sudhakar , Mula Suhrit , Narayan J. , Prater J. T.
Published: December 2012

We have introduced defects in ZnO (undoped and doped with Co and Mn) epitaxial thin films using laser irradiation from nanosecond laser pulses and thermal annealing in oxygen ambient. In contrast to the as grown samples, the laser irradiated films show a significant increase in conductivity, enhancement in UV emission, while maintaining the same wurtzite crystal structure. Room-temperature ferromagnetism (RTFM) is observed in laser-irradiated samples, which increased with the number of laser pulses up to a certain value where magnetic moment saturates. The induced ferromagnetism as well as the enhanced electrical conductivity can be reversed with thermal annealing in oxygen ambient. The magnetization in Co and Mn doped films was found to be strong function of growth conditions and defect concentration. X-ray diffraction and optical absorption experiments suggested a 2+ valance state and tetrahedral coordination for both Co and Mn ions. There is a simultaneous increase in n-type electrical conductivity with the number of laser pulses and continue to exhibit semiconducting behavior in both undoped and doped films. The saturation magnetization was found to be 0.08 μB/Co and 0.05 μB/Mn, much lower than 3.0 μB/Co and 5.0 μB/Mn, indicating the prominent role of intrinsic defects in RTFM with some contribution from Co2+-oxygen vacancy complexes. We propose a unified mechanism based upon introduction of intrinsic defects to explain RTFM and n-type conductivity enhancements during pulsed laser and thermal annealing.
Composition and morphology of self-organized Mn-rich nanocolumns embedded in Ge: Correlation with the magnetic properties
Authors: Mouton I. , Lardé R. , Talbot E. , Cadel E. , Genevois C. , Blavette D. , Baltz V. , Prestat E. , Bayle-Guillemaud P. , Barski A. , Jamet M.
Published: December 2012

The morphology and composition of self organized manganese (Mn)-rich nanocolumns embedded in germanium (Ge) thin films were characterized at the atomic scale and in three dimensions with high resolution transmission electron microscopy and atom probe tomography. Experiments revealed Mn-enriched nano-columns of 3 nm in diameter with various morphologies. Their Mn-content was found smaller than that of the expected equilibrium phases and chemical fluctuations along the growth axis were additionally observed. By contrast, less than 0.05% of Mn was measured in the Ge-matrix. These results were correlated to the magnetic properties and allowed understanding the magnetic behavior of the nanocolumns.
Terahertz scattering by two phased media with optically soft scatterers
Authors: Kaushik Mayank , Ng Brian W.-H. , Fischer Bernd M. , Abbott Derek
Published: December 2012

Frequency dependent absorption by materials at distinct frequencies in the THz range is commonly used as spectral-fingerprints for identification and classification. For transmission measurements, the substance under study is often mixed with a transparent host material. Refractive index variations arising from the presence of impurities and inconsistencies in the sample's internal structure often cause the incident radiation to scatter. This can significantly distort the measured spectral-fingerprints. In this letter, we present a numerical approach to allay the scattering contribution in THz-TDS measurements, provided the sample's refractive index is known, and reveal the true absorption spectra for a given sample.
Solvation of complex surfaces via molecular density functional theory
Authors: Levesque Maximilien , Marry Virginie , Rotenberg Benjamin , Jeanmairet Guillaume , Vuilleumier Rodolphe , Borgis Daniel
Published: December 2012

We show that classical molecular density functional theory, here in the homogeneous reference fluid approximation in which the functional is inferred from the properties of the bulk solvent, is a powerful new tool to study, at a fully molecular level, the solvation of complex surfaces and interfaces by polar solvents. This implicit solvent method allows for the determination of structural, orientational, and energetic solvation properties that are on a par with all-atom molecular simulations performed for the same system, while reducing the computer time by two orders of magnitude. This is illustrated by the study of an atomistically-resolved clay surface composed of over a thousand atoms wetted by a molecular dipolar solvent. The high numerical efficiency of the method is exploited to carry a systematic analysis of the electrostatic and non-electrostatic components of the surface-solvent interaction within the popular Clay Force Field (CLAYFF). Solvent energetics and structure are found to depend weakly upon the atomic charges distribution of the clay surface, even for a rather polar solvent. We conclude on the consequences of such findings for force-field development.
Experimental and theoretical studies on the electronic properties of vanadium-benzene sandwich cluster anions, VnBzn+1− (n = 1-5)
Authors: Masubuchi Tsugunosuke , Ohi Katsuya , Iwasa Takeshi , Nakajima Atsushi
Published: December 2012

Vanadium-benzene cluster anions, VnBzn+1− (Bz = C6H6) were generated by laser ablation and supersonic jet methods, and studied using photoelectron spectroscopy. The density functional theory was employed to compute their geometric and electronic structures. It is concluded that the VnBzn+1− anions exhibit multiple-decker sandwich structures similar to their corresponding neutrals, and the adiabatic electron affinity increases with the cluster size. Our computation shows that the excess electron of the anion occupies the d orbitals of the vanadium atoms and that it is delocalized one-dimensionally. Furthermore, a very large HOMO-LUMO gap difference between majority and minority spin orbitals is observed for both the neutrals and the anions, and the VnBzn+10/− clusters are found to be completely spin-polarized. These facts confirm the possibility of using VnBzn+1 clusters as spin filters.
Hysteretically reversible phase transition in a molecular glass
Authors: Kalkan B. , Sonneville C. , Martinet C. , Champagnon B. , Aitken B. G. , Clark S. M. , Sen S.
Published: December 2012

Pressure induced densification in a molecular arsenic sulfide glass is studied at ambient temperature using x-ray scattering, absorption and Raman spectroscopic techniques in situ in a diamond anvil cell. The relatively abrupt changes in the position of the first sharp diffraction peak, FSDP, and the pressure-volume equation of state near ∼2 GPa suggest a phase transition between low- and high-density amorphous phases characterized by different densification mechanisms and rates. Raman spectroscopic results provide clear evidence that the phase transition corresponds to a topological transformation between a low-density molecular structure and a high-density network structure via opening of the constituent As4S3 cage molecules and bond switching. Pressure induced mode softening of the high density phase suggests a low dimensional nature of the network. The phase transformation is hysteretically reversible, and therefore, reminiscent of a first-order phase transition.
Near-field simulation of obliquely deposited surface-enhanced Raman scattering substrates
Authors: Jen Yi-Jun , Suzuki Motofumi , Wang Yung-Hsiang , Lin Meng-Jie
Published: December 2012

A semicontinuous gold layer on a template with a zig-zag structure has been demonstrated to be a highly sensitive substrate for surface-enhanced Raman scattering (SERS). Obliquely deposited gold layers on different templates yield different SERS strengths. In this work, a finite-difference time-domain method is utilized to analyze the electric field distribution within the gold layer when the film is illuminated by light. The random gold nanostructures are scanned and transformed into binary images to allow them to be simulated. The field intensities and SERS enhancement factors of different samples are calculated and compared. Our analysis results reveal the near-field characteristics of strong SERS and agree closely with experimental measurements.
Thermal stability of the deep ultraviolet emission from AlGaN/AlN Stranski-Krastanov quantum dots
Authors: Himwas C. , Songmuang R. , Dang Le Si , Bleuse J. , Rapenne L. , Sarigiannidou E. , Monroy E.
Published: December 2012

We report on the structural and optical properties of AlGaN/AlN quantum dot (QD) superlattices synthesized by plasma-assisted molecular-beam epitaxy. Modifying the composition and geometry of the QDs, the peak emission wavelength can be shifted from 320 nm to 235 nm while keeping the internal quantum efficiency larger than 30%. The efficient carrier confinement is confirmed by the stability of the photoluminescence (PL) intensity and decay time, from low temperature up to 100 K. Above this threshold, the PL intensity decreases and the radiative lifetime increases due to carrier thermalization. We also identified the intraband electronic transition between the ground level of the conduction band and the first excited state confined along the growth axis (s-pz).
Development of vacuum ultraviolet absorption spectroscopy system for wide measurement range of number density using a dual-tube inductively coupled plasma light source
Authors: Kuwahara Akira , Matsui Makoto , Yamagiwa Yoshiki
Published: December 2012

A vacuum ultraviolet absorption spectroscopy system for a wide measurement range of atomic number densities is developed. Dual-tube inductively coupled plasma was used as a light source. The probe beam profile was optimized for the target number density range by changing the mass flow rate of the inner and outer tubes. This system was verified using cold xenon gas. As a result, the measurement number density range was extended from the conventional two orders to five orders of magnitude.
Collisionless electron heating by radio frequency bias in low gas pressure inductive discharge
Authors: Lee Hyo-Chang , Chung Chin-Wook
Published: December 2012

We show experimental observations of collisionless electron heating by the combinations of the capacitive radio frequency (RF) bias power and the inductive power in low argon gas pressure RF biased inductively coupled plasma (ICP). With small RF bias powers in the ICP, the electron energy distribution (EED) evolved from bi-Maxwellian distribution to Maxwellian distribution by enhanced plasma bulk heating and the collisionless sheath heating was weak. In the capacitive RF bias dominant regime, however, high energy electrons by the RF bias were heated on the EEDs in the presence of the ICP. The collisionless heating mechanism of the high energy electrons transited from collisionless inductive heating to capacitive coupled collisionless heating by the electron bounce resonance in the RF biased ICP.
Site-specific mapping of transition metal oxygen coordination in complex oxides
Authors: Turner S. , Egoavil R. , Batuk M. , Abakumov A. A. , Hadermann J. , Verbeeck J. , Van Tendeloo G.
Published: December 2012

We demonstrate site-specific mapping of the oxygen coordination number for transition metals in complex oxides using atomically resolved electron energy-loss spectroscopy in an aberration-corrected scanning transmission electron microscope. Pb2Sr2Bi2Fe6O16 contains iron with a constant Fe3+ valency in both octahedral and tetragonal pyramidal coordination and is selected to demonstrate the principle of site-specific coordination mapping. Analysis of the site-specific Fe-L2,3 data reveals distinct variations in the fine structure that are attributed to Fe in a six-fold (octahedron) or five-fold (distorted tetragonal pyramid) oxygen coordination. Using these variations, atomic resolution coordination maps are generated that are in excellent agreement with simulations.
Thermal stability of Au25− molecular precursors and nucleation of gold nanoparticles in thermosetting polyimide thin films
Authors: Bauld Reg , Hesari Mahdi , Workentin Mark S. , Fanchini Giovanni
Published: December 2012

We demonstrate that spherical gold nanoparticles of relatively narrow size distribution (250 nm size, 40 nm standard deviation) and gold microclusters (composed by smaller nanoparticles of 30–100 nm in size) can be obtained from in situ nucleation of Au25− molecules in polyimide at temperatures from 150 °C to 450 °C. Using scanning near-field optical microscopy and UV-visible spectroscopy, we demonstrate the presence of strong plasmonic resonance, which opens up a variety of applications in low-cost organic optoelectronics and plasmonics for our fully solution-processed thin films.
Gyrokinetic studies of the effect of β on drift-wave stability in the National Compact Stellarator Experiment
Authors: Baumgaertel J. A. , Hammett G. W. , Mikkelsen D. R. , Nunami M. , Xanthopoulos P.
Published: December 2012

The gyrokinetic turbulence code GS2 was used to investigate the effects of plasma β on linear, collisionless ion temperature gradient (ITG) modes and trapped electron modes (TEM) in National Compact Stellarator Experiment (NCSX) geometry. Plasma β affects stability in two ways: through the equilibrium and through magnetic fluctuations. The first was studied here by comparing ITG and TEM stability in two NCSX equilibria of differing β values, revealing that the high β equilibrium was marginally more stable than the low β equilibrium in the adiabatic-electron ITG mode case. However, the high β case had a lower kinetic-electron ITG mode critical gradient. Electrostatic and electromagnetic ITG and TEM mode growth rate dependencies on temperature gradient and density gradient were qualitatively similar. The second β effect is demonstrated via electromagnetic ITG growth rates' dependency on GS2's β input parameter. A linear benchmark with gyrokinetic codes GENE and GKV-X is also presented.