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Conducting polymer hydrogels combine electrical conductivity and tunable water content, rendering them strong candidates for a range of applications including biosensors, cell culture platforms, and energy storage devices. However, these hydrogels are mechanically brittle and prone to damage, prohibiting their use in emerging applications involving dynamic movement and large mechanical deformation. Here, we demonstrate that applying the concept of architecture to conducting polymer hydrogels can circumvent these impediments. A stereolithography 3D printing method is developed to successfully fabricate such hydrogels in complex lattice structures. The resulting hydrogels exhibit elastic compressibility, high fracture strain, enhanced cycling stability, and damage-tolerant properties despite their chemical composition being identical to their brittle, solid counterparts. Furthermore, concentrating the deformation to the 3D geometry, rather than polymer microstructure, effectively decouples the mechanical and electrical properties of the hydrogel lattices from their intrinsic properties associated with their chemical composition. The confluence of these new physical properties for conducting polymer hydrogels opens broad opportunities for a myriad of dynamic applications.

Three‐dimensional (3D) printing brings exciting prospects to the realm of conjugated polymers (CPs) and organic electronics through vastly enhanced design flexibility, structural complexity, and environmental sustainability. However, the use of 3D printing for CPs is still in its infancy and remains full of challenges. In this review, we highlight recent studies that demonstrate proof‐of‐concept strategies to mitigate some of these problems. Two general additive manufacturing approaches are featured: direct ink writing and vat photopolymerization. We conclude with an outlook for this thriving field of research and draw attention to the new possibilities that 3D printing can bring to CPs. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 1592–1605

Modified polyolefin separators fabricated via a roll-to-roll system exhibit markedly improved compatibility with lithium ion battery electrolytes. Zwitterionic molecules containing a perfluorophenyl azide functional group were synthesized and covalently bound to the surface of commercial polyolefin separators via UV-activated photochemistry. A roll-to-roll prototype system was constructed allowing for the functionalization of large areas of separator under ambient conditions at low cost. Lithium-ion battery cells containing the modified separators exhibit superior electrochemical performance using a common commercial electrolyte. The modified separators, both monolayer PE and trilayer PP/PE/PP, are wetted instantly upon contact with liquid electrolytes lacking linear carbonates. These electrolytes have been designed for use in batteries with advanced thermal stability properties and/or higher voltage windows, which have previously been hindered by incompatibility with commercial trilayer polyolefin separa...

We demonstrate a highly efficient thermal conversion of four differently substituted polydiacetylenes (PDAs 1 and 2a–c) into virtually indistinguishable N = 8 armchair graphene nanoribbons ([8]AGNR). PDAs 1 and 2a–c are themselves easily accessed through photochemically initiated topochemical polymerization of diynes 3 and 4a–c in the crystal. The clean, quantitative transformation of PDAs 1 and 2a–c into [8]AGNR occurs via a series of Hopf pericyclic reactions, followed by aromatization reactions of the annulated polycyclic aromatic intermediates, as well as homolytic bond fragmentation of the edge functional groups upon heating up to 600 °C under an inert atmosphere. We characterize the different steps of both processes using complementary spectroscopic techniques (CP/MAS 13C NMR, Raman, FT-IR, and XPS) and high-resolution transmission electron microscopy (HRTEM). This novel approach to GNRs exploits the power of crystal engineering and solid-state reactions by targeting very large organic structures th...

Summary We have developed a synthetic approach to graphene nanoribbons by using butadiyne-containing monomers that are initially converted to polydiacetylenes via topochemical polymerization in the crystal. Subsequent aromatization of the isolated polydiacetylenes at surprisingly mild temperatures affords graphene nanoribbons ∼1.36 nm in width with a 1.4 eV bandgap. These transformations take place solely in the solid state, in contrast to published on-surface or in-solution methods. This synthetic approach is well suited for electronic-device fabrication processes because it requires only UV light or heating and no external chemical reagents.

Cutting-edge synthesis is gradually delivering new types of graphene nanoribbons, enabling comparison of their properties to theoretical predictions. In this issue of Chem , Wu and coworkers describe oligomers of N = 5 armchair graphene nanoribbons possessing near-metallic ( E g = 0.21 eV) behavior.

This crisis over Berlin sparked Norstad to consider how best to coordinate NATO plans and policy in a situation in which the “rights” were non-NATO in origin, even though the “responsibilities” had become SACEUR’s. As recalled in the previous chapter, the three “Occupying Powers” — the US, the UK, and France — were still in Berlin by right of conquest. The other member-states of NATO had no direct involvement in the evolution of the status of Berlin stemming from the Yalta Declaration to its de facto partitioning.2 Consequently, in February 1959 Norstad directed the establishment at Headquarters USEUCOM of a “small concealed US only group as nucleus for any tripartite staff he might have to form.”3

Having come to Europe as Commander-in-Chief, US Air Forces, Europe (CINCUSAFE), Norstad was all too familiar with the problems and possibilities of creating an effective “nuclear umbrella” for NATO. Even though, as pointed out earlier, nuclear weapons played no formal part in the early planning of NATO, Norstad had emphasized that NATO could not just ignore them. He was convinced that a way must be found to give the European Allies a sense of sharing in the formulation of the doctrine for their employment and, if deterrence were to fail, their possible use. The issue, in a nutshell, was whether NATO nuclear proliferation should be unilateral or multilateral. In this respect, he had to work closely with the Federal Republic of Germany (FRG) as well as with France and Britain. As it was put: The relationship between the nuclearization of NATO and the settlement with the Federal Republic is not totally clear, but I suspect that there was an important link: nuclearization meant that the Americans, who controlled the most important forces and who in effect operated the strategy, would have to stay in Europe for a very considerable period of time, and as long as the Americans were in the French and many of the other allies could be relatively relaxed about a buildup of German power. Any possible German threat would be contained in a structure dominated by American power.2

In an effort not to lose sight of the long-term perspective while dealing with short-term problems, Arnold decided to create his own informal group of advisors to help him in long-range thinking. He had found that he was swamped with short-term problem-solving — or putting out brushfires. As he described it: My office organization in Washington contained an Advisory Council, a group of young men, the brightest I could get, who sat in an office close to me, and whose instructions were: “Don’t get mixed up with any routine business. What I want you to do is sit down and think. Think of the problems confronting us. Think of the solutions to those problems. Bring in new ideas. If you bring in one new idea every two or three days I will be satisfied. But don’t get mixed up with the routine operations of this office. Think! Think of the future of the Air Force!” That Advisory Council, made up changeably of anywhere from three to five officers, was invaluable to me. They brought me new ideas; kept me up-to-date, and best of all, made certain that I was very seldom caught off base by higher authority with any new problem before I had been able to give some thought to it.2

In December 1958, with tensions on the rise between the US and the USSR over Berlin, Dulles flew to Paris to attend the annual meeting of the NAC. While in Paris, he discussed with Norstad the possibility that Norstad should take certain “tightening up” actions that would not be lost on the Soviets.2 The source of tension arose from Chairman Khrushchev’s pronouncement of November 10, 1958 that he intended to sign a peace treaty “at an early date” with the German Democratic Republic (GDR), thus in his view terminating the Allies’ wartime rights in West Berlin. The official Soviet Note said: “the government of the USSR hereby notifies the United States Government that the Soviet Union regards as null and void the ‘Protocol of the Agreement between the Governments of the Union of Soviet Socialist Republics, the United States of America, and the United Kingdom on the zones of occupation in Germany and on the administration of Greater Berlin,’ of September 12, 1944, and the related supplementary agreements, including the agreements on the control machinery in Germany, concluded between the governments of the USSR, the USA, Great Britain, and France on May 1, 1945, i.e., the agreements that were intended to be in effect during the first years after the capitulation of Germany.”3

In order to facilitate rapid communications, Norstad reluctantly departed from his insistence that normal military command channels be followed in dealing with episodes over Berlin. He authorized the CINCUSAREUR, Lt. General Clarke, to communicate directly with the USCOB, Maj. General Watson. Norstad also insisted, of course, that he and his Deputy USCINCEUR, Lt. General Willis W. Palmer, be kept fully-informed about developments in Berlin.2 Norstad’s reasoning was that prompt decisions in the face of a Soviet-East German provocation were essential to stave off any sign of weakness or hesitation on the part of the Tripartite Powers. This deviation from normal communications procedure was to apply only to episodes in Berlin itself, and not to any activities on the autobahn. By giving operational control to CINCUSAREUR, located in Heidelberg, Norstad as USCINCEUR had removed himself from being directly involved in such decisions, unless there was a sharp change in the Berlin situation that might result in more extensive or unique responses than had already been authorized or contemplated.3

The negotiations over Berlin continued as the US presidency changed hands. A distinct difference, however, between the Eisenhower approach to European security and the Kennedy approach was the latter’s desire to show “strength,” and also to provide a “flexible response” concept rather than an — at least articulated — “all-or-nothing” concept to meet a Soviet threat to Berlin.2 For both reasons, it was obvious to the Kennedy Administration that more planning, effort and resources should be given to a conventional military buildup in Europe, even while not neglecting the nuclear dimension.

This is the story of a Supreme Commander and the institutions for which he served. These institutions doubtless contributed to the making of General Lauris Norstad. They certainly provided the opportunities that propelled his spectacular rise from very modest beginnings to become one of the leaders of the “Free World” at the height of the Cold War. In the course of this rise, his sharp and disciplined intellect and physical bearing brought him to the attention of powerful sponsors — General Henry H. “Hap” Arnold, the architect of the US Air force (USAF), and General Dwight D. “Ike” Eisenhower, the hero of World War II and a denning figure in the formation of the North Atlantic Treaty Organization (NATO).

Throughout the war, Arnold had been very sensitive to the public’s perception of the uses of air power. He wanted public opinion to assist him to move quickly, as soon as the hostilities ceased, to establish the Air Force as a separate and coequal Service with the Army and the Navy. This is one reason for his focus on “strategic” bombing as the central concept of Air Power doctrine, rather than on the use of air power in support of the land (or naval) battle. As he had written to Eaker in June 1943, when Eaker was Commanding General of the Eighth Air Force: It is also very important, for whole-hearted public and official support of our Air Forces in their operations, that the people understand thoroughly our Air Forces precepts, principles, and purposes … it is important for the people to understand that our prime purpose is destruction of the enemy’s ability to wage war, by our planned persistent bombing and sapping of his vital industries, his transportation, and his whole supply system …. In short, we want the people to understand and have faith in our way of making war.2 In December 1943, Major General Barney M. “Bennie” Giles, Arnold’s Chief of Staff, wrote: “We are devoting a great deal of thought to plans for the organization and composition of a postwar Air Force.

By January 1950 Norstad expected to leave his assignment as Air Force Deputy Chief of Staff for Operations, to replace Twining as Commander in Chief of the Alaska Command.2 But, as he said to Barton Leach: “I wouldn’t bet even money on it at this time.”3 Planning had been going rapidly forward as to how the US should confront the Soviet Union in Europe.4 It was becoming increasingly apparent that the loose structure created after the signing of the North Atlantic Treaty in April 1949 did not provide enough political reassurance as well as military security.5

The overarching theme of this chapter is that the basic confluence of the historical forces that have contributed to incessant European warfare is still very much with us. Even if we cannot agree entirely with Samuel Huntington’s thesis concerning the clash of civilizations, we can certainly understand that the ethnic/religious hatreds of the past are being revisited in the present.2 Additionally, we may be witnessing the gradual adaptation of the Cold War politics of Europe away from two (and then one) fixed coalitions, in the direction of shifting coalitions revolving loosely around various Great Power interests.

By the onset of this century, there had developed a form of bureaucratic organisation in international agencies that subsequently became the parent of modern international political organisations. On one hand, permanent staffs were created which carried out the purposes of agencies and gave them a sense of permanency and coherence. On the other, the staffs and their functions became separated from the governing bodies of the agencies, while some form of council set policy for the organisation. This policy-making process later was described as ‘conference diplomacy’.

Although unfortunate, crises are required to precipitate change in both domestic and international politics. Because assorted global crises have created greater awareness of global interdependence, various observers have concluded that international organizations will increasingly be given the responsibility for dealing with problems that formerly were in the exclusive purview of the nation-state. Evaluating the effectiveness of the United Nations system, and increasing an awareness of the functions and role of the United Nations, are among the main responsibilities of the United Nations Institute for Training and Research (UNITAR). UNITAR is now almost ten years old, and has just completed a reassessment of its priorities; therefore, it is an appropriate time to discuss its recent activities and to assess its prospects for the future.' UNITAR was established "for the purpose of enhancing . . . the effectiveness of the United Nations in achieving the major objectives of the Organization, in particular the maintenance of peace and security and the promotion of economic and social development."2 Although UNITAR's headquarters is in New York and most of the work of both the Training and Research Departments is centered there, increasing use is being made of the Institute's Geneva office. A significant number of training courses and seminars are now being conducted in Geneva and several of the

It is generally recognized that there are enormous difficulties, bureaucratic as well as political, that attend attempts to ameliorate human problems which arise from the growing interdependence of states. The policy challenge therefore is how to create—or alternatively, how to understand and then to reform—the existing machinery of international administration to enable it to cope with interdependence. The World Food Conference, held in Rome on November 5–16, 1974, was not only an exercise in ad hoc multilateral diplomacy designed to meet the immediate threats of the food crisis; it was also an attempt to rebuild the international food bureaucracy, either by replacing the Food and Agriculture Organization or by reforming it. The Conference largely succeeded in this task; it created a World Food Council, organizationally linked to the FAO in Rome, but separately responsible to the UN General Assembly through the Economic and Social Council. Thus, an examination of the leadership of the Secretariat of the World Food Conference provides a classic case for the study of bureaucratic politics: an international secretariat not merely indirectly influenced the shape of policy; it actually made policy.

What is Africa doing wrong? Africans as well as others are increasingly asking this question. We are, in effect, invited to consider that there are, perhaps, negative as well as positive aspects to the nation-building process in post-colonial Africa. To the layman, indeed, the image of Africa has tended to accentuate the negative. The strife in the Congo during the early 1960s, the civil war in Nigeria, numerous military coups d'etat and political assassinations, bureaucratic corruption, disappointing progress in the economic field, and more recently famine and drought, all could lead to the conclusion that efforts at nationbuilding have been less than successful.

Summary ACTH was administered as a diagnostic test to 41 patients with varioustypes of jaundice. No specific patterns of response were encountered and the previously describedusefulness of the test in the differential diagnosis of jaundice was not confirmed.

As the computer more and more becomes a tool to further quantitative political science research, the data analysis function threatens to overshadow the use of computers as information processors. Among the many functions of contemporary computer software is the ability to move text from user to user. These packages, available on almost any mainframe system, generally take the form of “electronic mail” systems and have proven invaluable for academics in communicating with each other around the world, making information thousands of miles distant seem located just around the corner.Mail systems do not diminish in utility even when used just around the corner. Users recognize the benefit of distant information acting as if of local origin, but should not miss the converse. Information local in nature, in using mail systems, can appear to originate from sources far away if the users choose to view the information in that fashion. In essence, mail systems provide the means to model a framework simulating interaction among international political actors.Thus the computer provides an ideal instrument to model diplomacy in the classroom and can aid instruction on the concept of diplomacy. When taken in the abstract, it seems difficult to teach diplomacy. Several questions arise concerning the concept's place in academia. First, why teach it? The answer lies in the state system. Nations behave as to achieve goals. War presents the starkest and most violent means to attain them, but nations often can eschew war and pursue goals by peaceful meansn—diplomacy. To creditably teach the behavior of nations requires investigation of diplomacy.

Great Powers employ a variety of maritime strategies, but these different national approaches have often been overlooked or inappropriately lumped together. Furthermore the concepts that were derived from these strategies can have effects that transcend the immediate historical circumstances that gave rise to them. Finally the methods of administration devised to implement governmental policy can either be viewed as a model for other rising Great Powers or can provide the means of making possible new institutions dealing with issues of concern to Great Powers. The purpose of this collection of essays is to examine the similarity in the Anglo-American perspective of Great Power maritime strategy and the role of navies in maintaining a balance of power. The institutions that emerged are very much a part of the life of all nations, great or small, and hence are worthy of careful examination.

In our view, the balance of power is a means to an end in international politics, not an end in itself. It is the means by which a state can prevent another from dominating world politics. At the same time, a balance of power creates a situation which allows a state to ensure its own safety and to promote its own interests and objectives. This system imposes limits on the degree and the range of objectives which a state can pursue, and this is true even if a state does not self-consciously pursue a balance of some sort. A balance of power is inherently self-limiting. It prevents hegemony by any single Power, and operates within the context of political pluralism.

The evolution of one of the most effective means of achieving some measure of multinational co-ordination and possible amelioration of international political rivalries took place as a consequence of the great colonial — or imperial — expansion of Great Britain into the non-European world. One result of this expansion was the Boer War in South Africa. In the wake of the generally poor performance of Britain in this war, and because of the growing awareness in London that the Empire needed more systematic overseeing, a means of co-ordinating Britain’s military affairs was introduced, called the secretariat method. In fact, stretching even from the Seven Years’ War, as Peter Nailor points out, a new concept of imperial security was slowly evolving: ‘The particular aspect of Imperial defense that pervades and illuminates the British experience is the cooperation (or lack of it) between the Imperial power and its self-governing possessions.’1 More to the point of this chapter, Nailor observes: … British Imperial defense is the story of a relationship that in some respects is more like that of an alliance than of central and dominant authority imposing and executing a series of objectives: a relationship in which persuasion and example — and indecision — have as much place as economic and political uncertainty or agreed strategic perspectives.2